IDENTIFYING FACTORS THAT INFLUENCE CHOICE OF STONE FOR THE
MANUFACTURE AND USAGE OF MAIZE GRINDING TOOLS IN ANCIENT MEXICO
Karen Deeann Watson
B.S., Wayne State University, Detroit, 1986
THESIS
Submitted in partial satisfaction of
the requirements for the degree of
MASTER OF ARTS
in
ANTHROPOLOGY
at
CALIFORNIA STATE UNIVERSITY, SACRAMENTO
FALL
2011
IDENTIFYING FACTORS THAT INFLUENCE CHOICE OF STONE FOR THE
MANUFACTURE AND USAGE OF MAIZE GRINDING TOOLS IN ANCIENT MEXICO
A Thesis
by
Karen Deeann Watson
Approved by:
__________________________________, Committee Chair
Martin F. Biskowski
__________________________________, Second Reader
David W. Zeanah
____________________________
Date
ii
Student: Karen Deeann Watson
I certify that this student has met the requirements for format contained in the University
format manual, and that this thesis is suitable for shelving in the Library and credit is to
be awarded for the thesis.
__________________________, Graduate Coordinator
Michael G. Delacorte
Department of Anthropology
iii
___________________
Date
Abstract
of
IDENTIFYING FACTORS THAT INFLUENCE CHOICE OF STONE FOR THE
MANUFACTURE AND USAGE OF MAIZE GRINDING TOOLS IN ANCIENT MEXICO
by
Karen Deeann Watson
Knowing what factors influenced pre-hispanic people’s choice of raw materials for
maize-grinding tools is important in increasing our understanding of intensified maize
preparation and changes in patterns of social, economic, and political development.
Analyzing data from several collections in three areas of Central Mexico, the Mezquital
Valley in Hidalgo, the Apizaco region in Tlaxcala, and the Teotihuacan Valley, Mexico, I
focused on three factors: durability, design of metate, and access to source material. In
general, it is not clear that durability of basalt grinding tools from the Apizaco region or
the Mezquital Valley can be measured by the combined attributes of stone density,
porosity, and texture quality. The design or style of the metate was important when
selecting raw material; stone for making Apizaco metates was chosen based on whether
the tools were made with feet. The middle Teotihuacan Valley site of Tlachinolpan was
not restricted to using solely nearby middle valley sources for making grinding tools. By
iv
the Late Formative/Terminal Formative Period, materials were being imported into the
Teotihuacan Valley.
_______________________, Committee Chair
Martin F. Biskowski
_______________________
Date
v
DEDICATION
To Tammie Mort (1961-2005), who took her spirit of adventure to a new level.
vi
ACKNOWLEDGEMENTS
First, I would like to thank my husband, Sean Haarsager, without whom I would
never have begun this project. Second, I would like to thank my mentor, Martin
Biskowski, without whom I would never have completed it. Richard Lesure and Patricia
Fournier, thank you for letting me use the Apizaco and Mezquital collections. Cheers to
all those at the lab at Teo for the workspace, the fun, and making me feel less homesick.
Thank you, Cristi Hunter and everyone in the CSUS Archaeology Lab for a great space in
which to work. David Zeanah, I appreciate you making me a top priority on such short
notice. A shout-out goes to Jessica Jones for letting me use the data from her
macroscopic geological examination. To all those others I have not specifically
mentioned, thanks for your help, encouragement and your friendship.
vii
TABLE OF CONTENTS
Page
Dedication ........................................................................................................................ vi
Acknowledgements ........................................................................................................... vii
List of Tables ..................................................................................................................... xi
List of Figures .................................................................................................................. xiii
Chapter
1. INTRODUCTION .......................................................................................................... 1
Apizaco........................................................................................................................................ 5
Tlachinolpan ................................................................................................................................ 6
Mezquital Valley ......................................................................................................................... 7
Summary ..................................................................................................................................... 8
2. LITERATURE REVIEW ............................................................................................. 10
Introduction ............................................................................................................................... 10
Importance of Grinding Tools in Prehispanic Societies ............................................................ 10
Formal Description/Analysis Studies (Morphology, Function, Typology, Style)..................... 14
Source Analysis Studies ............................................................................................................ 20
Raw Material Selection ............................................................................................................. 24
Other Relevant Studies .............................................................................................................. 26
Regional Prehistory and Grinding Tool Analyses within Each Region .................................... 35
3. METHODS OF ANALYSIS ........................................................................................ 42
Artifact Attribute Analysis ........................................................................................................ 42
Geochemical Analysis ............................................................................................................... 45
viii
Summary ................................................................................................................................... 51
4. RESULTS ..................................................................................................................... 52
Factors Determined by Artifact Attribute Analysis................................................................... 52
Factors Determined by Geochemical Analysis ......................................................................... 75
Summary ................................................................................................................................... 80
5. DISCUSSION AND CONCLUSIONS ........................................................................ 82
Durability .................................................................................................................................. 82
Design or Metate Type .............................................................................................................. 84
Tlachinolpan Stone Sources ...................................................................................................... 85
Summary ................................................................................................................................... 86
Appendix A Mezquital Valley Mano Density, Porosity, Texture Quality Data,
Frequencies, and Percentages. ...................................................................... 88
Appendix B Mezquital Valley Metate Density, Porosity, Texture Quality Data,
Frequencies, and Percentages. ...................................................................... 91
Appendix C Apizaco Mano Density, Porosity, Texture Quality Data, Frequencies, and
Percentages. .................................................................................................. 93
Appendix D Apizaco Metate Density, Porosity, Texture Quality Data, Frequencies, and
Percentages. .................................................................................................. 96
Appendix E Basic Grinding Tool Form ............................................................................ 99
Appendix F Sample Mano Form..................................................................................... 100
Appendix G Sample Metate Form .................................................................................. 102
Appendix H Principal Components Analysis For Apizaco Artifacts ............................. 103
ix
Appendix I Tlachinolpan Source Assignment Analysis ................................................. 111
References Cited ............................................................................................................. 127
x
LIST OF TABLES
Page
1.
Table 1. Sites and Associated Periods. ................................................................... 4
2.
Table 2. Apizaco Metates Stone Density g/ml. Apizaco Sites in Bold.
Comparative Sites from Biskowski (1997). ............................................ 55
3.
Table 3. Apizaco Manos Stone Density g/ml. ...................................................... 56
4.
Table 4. Apizaco Metates Mean Porosity Scores. Ordinal Scale of 0 to 5; 0 = No
Pores and 5 = Very Porous. Apizaco Sites in Bold. Comparative Sites
from Biskowski (1997). .......................................................................... 57
5.
Table 5. Apizaco Manos Mean Porosity Scores. Ordinal Scale of 0 to 5; 0 = No
Pores and 5 = Very Porous. Apizaco Sites in Bold. Comparative Sites
from Biskowski (1997). .......................................................................... 59
6.
Table 6. Apizaco Metates Mean Texture Quality Scores. Ordinal scale of 0 to 2; 0
= Vesicular, 1 = Medium, and 2 = Granular. .......................................... 60
7.
Table 7. Apizaco Manos Mean Texture Quality Scores. Ordinal scale of 0 to 2; 0
= Vesicular, 1 = Medium, and 2 = Granular. .......................................... 61
8.
Table 8. Summary of Apizaco Metate Attribute Means. ...................................... 63
9.
Table 9. Summary of Apizaco Mano Attribute Means. ........................................ 63
10.
Table 10. Summary of Mezquital Valley Mano and Metate Attribute Means. .... 64
11.
Table 11. Mezquital Valley Manos Mean Density g/ml. ...................................... 71
12.
Table 12. Mezquital Valley Metates Mean Density g/ml. .................................... 71
xi
13.
Table 13. Mezquital Valley Mean Density Two Sample T-test, Manos Compared
to Metates .............................................................................................. 72
14.
Table 14. Mezquital Valley Manos Mean Porosity Scores. Ordinal Scale of 0 to 5;
0 = No Pores and 5 = Very Porous. ...................................................... 72
15.
Table 15. Mezquital Valley Metates Mean Porosity Scores. Ordinal Scale of 0 to
5; 0 = No Pores and 5 = Very Porous. .................................................. 73
16.
Table 16. Mezquital Valley Manos Mean Texture Quality Scores. Ordinal scale of
0 to 2; 0 = Vesicular, 1= Medium, and 2 = Granular. ........................... 73
17.
Table 17. Mezquital Valley Metates Mean Texture Quality Scores. Ordinal scale
of 0 to 2; 0 = Vesicular, 1= Medium, and 2 = Granular. ...................... 74
18.
Table 18. Apizaco Metates Grouped by Source. .................................................. 75
19.
Table 19. Stone Source Assignments for Late/Terminal Formative and Classic
Period Sites in Teotihuacan Valley. All Data Except Those for
Tlachinolpan Are from Biskowski 1997. .............................................. 79
xii
LIST OF FIGURES
Page
1.
Figure 1. Sites mentioned in this study. .................................................................. 4
2.
Figure 2. Drying oven with mortars and pestles. Photos by Cristi Hunter. .......... 47
3.
Figure 3. Teotihuacan Valley sites and fingerprint source sampling areas
(Biskowski, et al. 1999; Watson, et al. 2006). Map created by Martin
Biskowski. ............................................................................................. 49
4.
Figure 4. Teotihuacan Valley source fingerprints (Log Th vs. Log Cr). .............. 50
5.
Figure 5. Apizaco metate density frequencies g/ml. ............................................. 54
6.
Figure 6. Apizaco mano density frequencies g/ml................................................ 54
7.
Figure 7. Apizaco metate porosity frequencies..................................................... 57
8.
Figure 8. Apizaco mano porosity frequencies. ..................................................... 58
9.
Figure 9. Apizaco metate texture quality frequencies. ......................................... 60
10.
Figure 10. Apizaco mano texture quality frequencies. ......................................... 61
11.
Figure 11. Mezquital Valley metate density frequencies g/ml. ............................ 65
12.
Figure 12. Mezquital Valley mano density frequencies g/ml. .............................. 66
13.
Figure 13. Mezquital Valley metate porosity frequencies. ................................... 67
14.
Figure 14. Mezquital Valley mano porosity frequencies. ..................................... 68
15.
Figure 15. Mezquital Valley metate texture quality frequencies. ......................... 69
16.
Figure 16. Mezquital Valley mano texture quality frequencies. ........................... 70
17.
Figure 17. Middle Formative Period Apizaco slab metates with supports or feet
from Tetel.............................................................................................. 77
xiii
18.
Figure 18. Apizaco metates from Tetel and La Laguna........................................ 77
xiv
1
Chapter 1
INTRODUCTION
Ethnographic sources have shown that modern metateros (those who make stone
maize-grinding tools) find some physical characteristics of stone more desirable than
other characteristics for making and using manos and metates (Adams 1993; Cook 1982;
Hayden 1987a, 1987b, 1987c; Hayden and Cannon 1984; Horsfall 1987; Mauldin 1991,
1993; Searcy 2005:58-60). According to Hayden (1987c:14-17) some of the more
durable stone tools are more difficult to make. Softer stone is easier to work with but is
less durable. As in modern times, people from prehistoric societies of Central Mexico
preferred certain physical characteristics of stone for their grinding tools. This study uses
archaeological evidence to identify some of the factors that influenced raw material
selection. For example, patterns of exchange, quarry location, tool use, tool durability,
tool discard, and secondary usage may have influenced the production of grinding tools.
This thesis focuses on the following three factors:
(1) Did durability influence the choice of stone for the production of manos
and metates?
(2) Was the design or type of metate important when selecting raw material?
(3) Were some sites restricted to certain stone sources?
More detail regarding these factors appears later in this chapter.
Why people chose one stone over another for their tools is a very important part
in understanding past cultures and tool design strategy. “[U]nderstanding the material
properties of tools provides the critical link between the environment and how people
2
employed concepts to alter the environment” (Hayden 1987c:13). Knowing what factors
influenced people’s selection of raw materials for maize-grinding tools is important in
increasing our understanding of maize preparation intensification and changes in patterns
of social, economic, and political development (Biskowski and Watson 2007, 2008;
Schneider and LaPorta 2008).
Maize-grinding tools consist of a pair of ground stone tools called the mano and
the metate. The mano is the active grinding stone held in the hand and ground against the
passive metate surface. These tools were an irreplaceable part of Mesoamerican
domestic technology. Ethnographic records show that women spent hours grinding limesoaked maize kernels, called nixtamal, into masa for tortillas and other products.
Additional research documents the multitude of alternative or secondary uses of these
artifacts in domestic contexts (Hayden 1987b). The large number of these artifacts found
at early settlement sites indicates how important these tools were to the prehispanic
people of Central Mexico.
One problem that makes any analysis of maize-grinding tools difficult is the low
number of these artifacts found in archaeological collections. As has been noted in other
studies, archaeologists before the 1980s often did not make substantial efforts to collect
grinding tools when in the field (Biskowski 2008) (some exceptions are George
Vaillant’s work, work at Portezuelo, and the Teotihuacan Mapping Project). This is not
surprising considering how heavy these tools can be. For example, a particular metate
fragment in one of the collections used in this study weighs about 17 kg and the original
metate was heavier still. Even when archaeologists make conscious efforts to collect
3
grinding tools, there are not that many to be collected compared to other artifacts, such as
ceramics. Both Hayden (1987b:191-197) and Cook (1982:309) indicated that, in general,
residents in a household replaced their metates only about once in every 15 to 30 years.
Thus, the low number of these artifacts in archaeological collections makes analyzing
maize-grinding tools challenging.
As stated earlier, this study will identify factors that apparently influenced the
choice of raw material for the manufacture and usage of maize-grinding tools in ancient
Mexico. This thesis is part of an ongoing study of maize-grinding tools and maize
preparation intensification in Central Mexico (Biskowski 1997, 2000, 2004, 2008;
Biskowski et al. 1999; Biskowski and Watson 2007, 2008; Gueyger and Biskowski 2005;
Watson et al. 2006).
This study focuses on three areas in Central Mexico: the Apizaco region in the
state of Tlaxcala, the site of Tlachinolpan in the Teotihuacan Valley in the state of
Mexico, and the Mezquital Valley in the state of Hidalgo (Figure 1). Collections from
these areas span the Formative Period through the Epiclassic Period and later (Table 1).
These periods cover the time through and beyond the rise and fall of the city of
Teotihuacan. Studying grinding tools from these periods could show what adaptations
people made during the development of state level societies. Analysis of tools from these
areas can also provide information about patterns of exchange, comparisons of local
patterns of stone usage, regional differences in production, and a better understanding of
the changes in the intensification of maize preparation through the Formative, Classic,
and Epiclassic Periods.
4
Figure 1. Sites mentioned in this study.
Table 1. Sites and Associated Periods.
SITE
Amomoloc
Tetel
La Laguna
LOCATION
Apizaco Region
Apizaco Region
Apizaco Region
Las Mesitas
Tlachinolpan
Cuanalan
Tezoyuca
Venta de Carpio
Maquixco Bajo
Chapantongo
Tula
Apizaco Region
Teotihuacan Valley
Teotihuacan Valley
Teotihuacan Valley
Teotihuacan Valley
Teotihuacan Valley
Mezquital Valley
Mezquital Valley
PERIOD
Middle Formative
Middle/Late Formative
Late Formative
Terminal Formative
Late/Terminal Formative
Late/Terminal Formative
Late Formative
Early Terminal Formative
Late Terminal Formative
Classic
Epiclassic
Epiclassic/Postclassic
5
Apizaco
Several sites located in Tlaxcala represent the Apizaco study region: Amomoloc,
San Jose Tetel, La Laguna, and Las Mesitas. These sites are chronologically sequential
with Amomoloc being the earliest site and Las Mesitas being the latest site (see Table 1).
La Laguna did have a second occupation later than Las Mesitas. However, none of the
La Laguna grinding tools used in this study had dates associated with the later
occupation. The occupational dates of the sites are distinct but have some overlap.
Richard Lesure and his students made the collections as part of a UCLA project entitled
“Investigaciones del Formativo en la Región de Apizaco, Tlaxcala” (Borejsza 2006;
Borejsza et al. 2008; Carballo 2005, 2006; Lesure 2007; Lesure et al. 2006). Lesure and
his team were looking to confirm the chronology of Apizaco and to investigate the
beginnings of agriculture in this region (Lesure et al. 2006).
Previous analyses of grinding tools from this region identified changing patterns
of intensive maize preparation (Biskowski and Watson 2007; Gueyger and Biskowski
2005). According to Gueyger and Biskowski (2005), the earliest sign of increased
intensive maize grinding occurs with the appearance of footed metates. At the same time
that the footed metates appear, there is a shift toward the use of more coarsely textured
stone. Since one would expect a finer textured stone for more intensive grinding there
must be some reason that these people chose coarse stone instead. One possibility is that
coarse stone texture was a side effect of a concern for durability (Biskowski and Watson
2007). Examining durability in the various Apizaco sites provides a better understanding
of how this factor influenced the choice of raw material over time.
6
Intensification of grinding tool use reflects either local or external influences
toward the production of better processed, more nutritious maize foods. Gueyger and
Biskowski (2005) hypothesized that changes in metate forms indicate increasing food
production, possibly reflecting the Apizaco region becoming tributary to Teotihuacan.
Standardized tool forms and raw materials may indicate a standard, consistent method of
preparing maize. Further analysis will clarify if grinding tools were part of patterns of
exchange that earlier studies identified (Biskowski 1997; Biskowski et al. 1999; Carballo
et al. 2007; Carballo and Pluckhahn 2007; Watson et al. 2006). For example, evidence
indicated that grinding tool exchange between the Mezquital Valley and other regions
was unlikely, whereas exchange of these items between Teotihuacan and the Apizaco
region was plausible (Watson et al. 2006). Evidence suggesting that footed metates came
from different quarries than non-footed tools can help in understanding these patterns in
the Apizaco region.
Tlachinolpan
Tlachinolpan is a Formative Period site in the middle section of the Teotihuacan
Valley in the state of Mexico. The Tlachinolpan collection dates to the Cuanalan,
Patlachique, and Tzacualli phases of the Late Formative Period (Blucher 1971) and
comes from an administrative center just outside of the later city of Teotihuacan. The
purpose of excavations here was to increase our understanding of the Patlachique Phase
in order to understand the factors that led to the evolution of the state of Teotihuacan
(Blucher 1971:5-6). The analysis of this middle Teotihuacan Valley collection provides
the opportunity to compare early patterns of stone usage with patterns observed
7
previously at contemporary sites in the lower Teotihuacan Valley, such as Cuanalan,
Tezoyuca, and Venta de Carpio (Biskowski 1997) and to contrast patterns found at the
middle valley site of Maquixco Bajo (Biskowski et al. 1999). Tlachinolpan is noteworthy
for its standardized, well-made maize-grinding tools, which may indicate a standardized
method of maize preparation. Maize-grinding tools that are more complex and finished
imply that metateros were skilled craftsmen and not just occasional, opportunistic
manufacturers. Additionally, better tools suggest more intensive grinding taking place.
Diversity of raw material usage shows that Teotihuacan’s growing population needed
more resources. On the other hand, the use of fewer resources may be a symptom of
regulation of production. For these reasons, it is important to try to identify, through
geochemical analysis, raw material sources for these grinding tools.
Mezquital Valley
The Mezquital Valley region is located in the state of Hidalgo. The collection
includes artifacts from Chapantongo, Tepetitlan, and several other sites. Chapantongo
and Tepetitlan are rural villages located near the Toltec capital city of Tula. Patricia
Fournier and her team (Fournier 2001; Fournier and Bolaños 2007; Fournier and Pastrana
1999) collected the artifacts as part of the Proyecto Distrito Alfarere del Valle de
Mezquital. The artifacts date to the Epiclassic Period. The purpose of this project was to
compare and contrast the prehispanic settlement and social interaction in the Mezquital
Valley and the Teotihuacan Valley (Rodríguez et al. 2000).
Preliminary examination of the artifacts shows a difference in the pattern of
grinding tool use between the city and the rural areas. Upon examining the photos of
8
metates from Stroh (1975), the artifacts from Tula are more consistent in both form and
material. This indicates a highly specialized grinding tool industry with a focus on
intensive maize preparation. The rural artifacts show a mix of raw materials and a variety
of metate shapes, including one with a square foot as opposed to conical feet. This is
consistent with a more opportunistic usage of raw materials and possibly a less intensive
usage of maize, which seems to be characteristic of Epiclassic and Early Postclassic sites
(Biskowski and Watson 2008). Analysis of the Mezquital Valley collection supports the
rural usage pattern. Again, identifying the importance of durability as a factor in
choosing raw materials for grinding tools will provide more evidence for this
interpretation.
Summary
To restate the purpose of this thesis, this study identified factors that influenced the
choice of raw materials for the manufacture and usage of maize-grinding tools from
ancient Mexico. The collections studied come from several sites in Apizaco, Tlaxcala;
from the site of Tlachinolpan in the Teotihuacan Valley; and from several sites in the
Mezquital Valley. In particular, this paper answers three questions:
(1) Did durability influence the choice of stone for the production of manos
and metates in the Apizaco region or in the Mezquital Valley?
(2) Was the design or type of metate important for Apizaco metateros when
selecting raw material?
(3) Was Tlachinolpan restricted to using nearby middle Teotihuacan Valley
stone sources for the production of maize-grinding tools?
9
Answering these three questions will contribute to our understanding for a multi-regional
perspective of patterns of exchange and the changing patterns of maize preparation
intensification in prehispanic Mexico.
10
Chapter 2
LITERATURE REVIEW
Introduction
Grinding tools have been embedded in prehispanic cultures since before
agriculture and the domestication of maize. Over time, the mano and metate became
essential for preparing maize for consumption. They also became important items for
production and exchange. They even appear as grave goods. The first section of this
chapter provides an overview of some of the different ways maize-grinding tools are
embedded in prehispanic cultures. The next section discusses morphological,
typological, functional, and stylistic studies. The third section includes geochemical and
source analyses. The fourth section reviews some pertinent raw material selection
studies. The last section covers regional studies germane to the geographical areas of this
study.
Importance of Grinding Tools in Prehispanic Societies
Grinding tools were an important part of the toolkit of prehispanic peoples from
the times of hunter-gatherers. These tools became even more important as the huntergatherers transitioned to a more sedentary lifestyle. Niederberger (1979) noted increasing
numbers and standardization of grinding tools at the site of Zohapilco between the Playa
phase (6000-4500 BC) and the Zohapilco phase (3000-2200 BC) of the Archaic Period.
The observed increase in skill level “suggested a marked tendency toward craft
specialization” (Niederberger 1979:138). The number of mano and metate fragments
found increased until the Manantial phase then decreased through the Zacatenco and
11
Ticomán phases (Niederberger 1976).
The development of more standardized grinding tools coincided with a change in
teosinte seed. According to Niederberger, there is evidence that, in Zohapilco during the
Playa phase, people protected teosinte seeds, most likely the predecessor to modern
maize. In the Zohapilco phase, teosinte showed an increase in size and a three-fold
increase in frequency (Niederberger 1979). This suggests a connection between maize
and grinding tools at a very early date, even before maize was an important part of the
diet.
MacNeish (1971) postulated a similar connection between grinding tools and the
advent of maize agriculture in the Tehuacán Valley. The Tehuacán Valley, located in
Puebla about 150 miles south of Mexico City, has provided some of the earliest evidence
for the domestication of maize. Evidence of the earliest plant gatherers in this valley
dates to the Ajuereado phase of the Archaic Period (12,000-7600 BC). Plant gathering
grew in importance over time. Milling stones became more prevalent during the El
Riego phase (7200-5200 BC). MacNeish (1971) states that milling stones of the El Riego
phase became true manos and metates in the Coxcatlan phase (5200-3400 BC). Although
people were still hunter-gatherers in the Coxcatlan phase, MacNeish said these tools
indicate an economic shift toward maize agriculture (MacNeish 1992:95).
During the Early Formative Period, which followed the Archaic Period, there is
evidence that grinding tools in Mesoamerica were important not just for preparing food
but also for providing items for exchange. Archaeologists have suggested that Coapexco
and Loma de Atoto were craft centers for production of grinding tools (Tolstoy et al.
12
1977). Coapexco, in the southern part of the state of Mexico, was a permanent settlement
that dates to about 1150 BC (Tolstoy 1975; Tolstoy et al. 1977). The location, in the
Amecameca Pass at about 2600m elevation, is unusual for a settlement in Mesoamerica at
any time. Settlement occupation lasted for about 100 or 200 years. Obsidian from
Otumba, found at the site, indicated a regional distribution system. The forms of
evidence for craft specialization in the manufacture of manos and metates for distribution
are as follows:
(1) there are both incomplete tools and completed, unused tools at the site;
(2) the tool-makers used local raw material;
(3) artifacts were found in a non-residential distribution pattern;
(4) there is an unusually high ratio of grinding tool fragments to pottery
sherds (Tolstoy et al. 1977).
Loma de Atoto may have been a Middle Formative (750 – 425 BC) craft center
for maize-grinding tools (Tolstoy et al. 1977). This site is located in the Basin of Mexico
overlooking the plain at Tlatilco (Tolstoy and Fish 1975). Again, the evidence for
specialized production is the high ratio of grinding tools to sherds as compared to other
sites. Although the evidence from Loma de Atoto is indicative of possible specialized
production, it is not as convincing as the evidence from Coapexco, because the ratio is
not as high at Loma de Atoto as at Coapexco.
Archaeologists have interpreted the La Libertad site in Chiapas, Mexico, as a
regional center that flourished about the same time as Loma de Atoto. John Clark (1988)
used information from modern ethnographies (e.g., Cook 1982; Hayden 1987a) when
13
interpreting stone tools from Middle Preclassic, i.e., Middle Formative, (700-300 BC) La
Libertad. Clark’s goal was to discover what kind of cultural information could be
gleaned from the study of prehistoric stone tools. He looked at many aspects of the tools,
such as materials, consumption, production, and exchange. The author wanted to
determine the material source, the manufacturing techniques, and the functionality. His
focus was on the primary use of the tools. Clark formed his economic perspective of the
area from his findings.
As noted above, La Libertad seems to have been a regional center during the
Middle Formative. Based on the distribution of culturally distinct artifacts from the
surrounding regions, they participated in an exchange network that stretched from Las
Delicias to the Guatemala Highlands (Clark 1988:5-9, 158-160). The grinding tools were
made in mostly non-local areas and imported as completed products. The non-local tools
came from at least five different sources, none of which is very far from La Libertad. It
is important to note that the amount of reuse of broken grinding tools indicates how
valuable these tools were to the Prehispanic household (Clark 1988:133).
Another example of the value of maize-grinding tools is their use as grave goods.
To keep this paper a reasonable length, this chapter will highlight only a few of the many
documented occurrences.
Tolstoy (1989) found that at Tlatilco, an Early Formative site in the Basin of
Mexico, manos and metates were used as grave goods but not as expected. Manos
clearly marked female burials, but metates appeared with projectile points, which are
usually markers for male burials. Metates were also used as grave goods at Aljojuca in
14
Puebla, Las Colinas in Tlaxcala, and Tlamimilolpan in Teotihuacan (Linné 2003). Delu
(2007) states that the Postclassic Maya used grinding tools as grave goods with all age
groups except adolescents in Caye Coco, Belize. These four sites cover a variety of time
periods and locations. The depth and breadth illustrates the significance of grinding tools
throughout Mesoamerican culture.
The fact that maize-grinding tools are deeply embedded in ancient Mesoamerican
culture highlights the criticality of studying these artifacts. As there are many different
ways that manos and metates are a part of culture, so there are many different ways to
study them. The next sections discuss the different methods of studying maize-grinding
tools that pertain to this thesis.
Formal Description/Analysis Studies (Morphology, Function, Typology, Style)
Working at several sites in Mexico (Zacatenco, Ticoman, El Arbolillo,
Gualupita), George Vaillant created a typology of manos and metates by comparing the
various morphologies (Vaillant 1930, 1931, 1935; Vaillant and Vaillant 1934). He then
used the typology to suggest that different tools were used during different time periods.
Using ceramics, he tied tool types to time periods. Paul Tolstoy (1971) continued
Vaillant’s work and corrected some of the chronology for the tools. Niederberger (1976)
used these typologies to identify and date the grinding tools she encountered in
Zohapilco. Blucher (1971), who worked at Tlachinolpan, which is near Teotihuacan in
the Valley of Mexico, provided descriptions of grinding tools with comparisons to the
Vaillant types. Castañeda Saldaña (1976), who worked in Teotihuacan, built her types
15
upon Garcia Cook’s scheme (García Cook 1967). These morphological and typological
studies provide a basis for comparing maize-grinding tools across the Basin of Mexico.
In 1993, Adams studied the technological developments of manos and metates in
the southwestern United States to find evidence that “morphological variation in manos
and metates has behavioral and social implications” (Adams 1993:331). She defines
technology as the solution to a problem or a way to reach a goal. In the Southwest, those
who made the grinding stones either were the same individuals as, or closely related to,
those who used the grinding stones. This means that knowledge passed between these
individuals with few barriers (Adams 1993).
Manos and metates were the technological solution for the problem of how to
make flour from grain. These tools became the first formalized food-grinding tool kit.
Trough metates with shorter manos provided a new solution to a new problem. Flat
metates with longer manos did the same. According to Adams, archaeologists thought
the morphological changes, especially from trough to flat metates, represented an
increased reliance on maize to meet the dietary needs of a growing population.
Adams examined three types of metates for grinding efficiency and intensity. She
defines grinding efficiency as the amount of effort expended when grinding while effort
is the amount of energy used or amount of time spent. Intensity is the amount of time
expended in a single grinding episode. Increased efficiency can translate to “less time
spent grinding to feed the same number of people the same amount of grain”. It also can
translate to the “same amount of time spent grinding to feed more people or to increase
the amount of grain in the diet”. More intensity means “more time spent at the grinding
16
task either to feed more people or to increase the amount of grain in the diet” (Adams
1993:333,334). However, Adams is comparing the efficiency of generating the same
amount of product using different kinds of metates. She does not measure the amount of
time needed to produce finer flour over coarser flour.
The ethnographic descriptions to which Adams had access only provided data to
examine grinding strokes for flat metates. These ethnographic descriptions of wear
patterns are important because it shows that users were aware that manos wore unevenly
with prolonged use and therefore created use-wear management skills. Users could
manage wear to adjust for comfort or to increase use-life. Because of the lack of
ethnographic accounts for the other mano-metate types, the author experimented with the
stroke on all three types: basin metate with a one-handed mano, trough metate with a
short two-handed metate, and flat metate with a long two-handed metate.
Adams found that the basin metate was the least energy efficient, yet one could
alter the stroke to reduce muscle stress. The trough metate crushed more kernels quicker
than the basin. With the trough, the user could apply more force using both hands,
shoulders, and back, but one could not change the stroke. With the flat metate, one could
alter the stroke and use both hands, but would need a receptacle to catch spillage.
Based on her results, Adams suggests that the switch from a basin to a trough
metate could have happened for different reasons at different times in the Southwest.
One may have switched from a basin to a trough metate to either grind more grain or
generate some free time. Switching to a flat metate may have occurred when a user
needed to spend more time grinding. In addition, increased grinding efficiency and
17
intensity may not have happened at the same time everywhere. The number of grinding
surfaces per mano may indicate the level of intensity and wear management. Different
grinding tool shapes could result from different grinding techniques, personal
preferences, available raw materials, and learned behaviors such as increased efficiency
and managing use-life (Adams 1993:342). This study shows how morphological changes
in grinding tools can reflect culture evolution in an informative way.
With the concept of cultural evolution in mind, Biskowski (1997) examined the
artifact attributes of manos and metates in the Teotihuacan Valley, in Mexico, for
morphological changes that could provide evidence regarding the evolution of early
markets. Markets provide a place for the craft specialist to provide goods to exchange
partners. Biskowski states that artifact attributes of maize-grinding tools can provide a
“basis for the study of energy and expertise invested during craft production” (Biskowski
1997:16-17). He notes that the manufacture, exchange, and consumption of manos and
metates, as well as the method of usage to prepare foods, are features of the subsistence
economy that can inform about the relationships between subsistence goods and market
formation.
To that end, Biskowski analyzed the attributes of manos and metates from several
different collections in the Basin of Mexico. There were several collections from the
Teotihuacan Valley, which includes the Teotihuacan Mapping Project, the Teotihuacan
Valley Project, the Pyramid of Quetzalcoatl, and several other collections; a collection
from Otumba; and a collection from the Temascalapa region (north of Cerro Gordo). The
author predicted how the shape and workmanship of metates reflect factors that
18
influenced early market formation. The introduction of lime-treatment should result in
metates with flatter, more open grinding surfaces. In addition, intensive maize
preparation benefits from better quality tools. Thus, expertise and manufacturing cost
will be evident in stone tools. Finally, finer, less porous stone serves as the raw material
for manos and metates (in order to obtain a finer grind). The following is a partial list of
the artifact attributes that Biskowski used to test his predictions: stone porosity, dorsal
concavity of the metate, and stone density or specific gravity measured as grams per
milliliter.
Biskowski noted several trends over time. Formative Period metates were more
concave than the flatter Classic Period metates, suggesting that lime-treatment did not
arise until the early Classic Period (Biskowski 1997:308-312). Regarding stone porosity,
metates from the Formative and Classic Periods had coarse or medium texture while later
metates were more finely textured. Finally, from the Formative Period through the
Classic and possibly into historic times, metates definitely decline in average density
(specific gravity). Although this is a simplified summary of Biskowski’s results, it shows
that analyzing artifact attributes of grinding tools can reveal larger social and economic
processes such as early market formation.
Another example of the use of artifact attribute analysis (Gueyger and Biskowski
2005) examined the morphology of maize-grinding tools from Formative Apizaco,
Tlaxcala in Mexico for evidence of increased dependence on maize. The authors used
collections from four sites in Apizaco: Amomoloc (900-600 BC), Tetel (700-400 BC),
Las Mesitas (500-350 BC), and La Laguna (600-400 BC & 100 BC- AD 100). More
19
information about this region and their collections appears later in this chapter since these
collections provided part of the data upon which this thesis is based. Using artifact
attribute analysis, the authors set out to identify whether intensive maize preparation
occurred in this region and if it did, when the intensification occurred. The authors found
at least three attributes that indicate intensified food preparation. They noted flatter
grinding surfaces over time and the increased use of feet or supports on the metates, as
well as an increase in used surface area on the manos. A flat metate surface is more
effective for fine grinding. A raised surface can also increase grinding efficiency
(Gueyger and Biskowski 2005). By comparing grinding tool attributes from site to site,
the authors found evidence that, in general, maize preparation did intensify over time.
Mauldin’s studies also found ties between the grinding surface area of grinding
tools and agricultural intensification in the American Southwest (Mauldin 1991, 1993).
Analyzing changes in ground stone collections from Pine Lawn Valley, the author noted
that agricultural intensity is connected to the number of multi-sided manos, increased size
of manos, and changes in the shapes and styles of metates (Mauldin 1993). As
dependence on agricultural produce increased in the Mogollon Highlands, manos became
longer (Mauldin 1991), in order to provide more grinding surface area. One can apply
the information gathered from this study to the analysis of maize-grinding tools
anywhere, including Mesoamerica.
From ethnographic studies, Clark (1988) determined that different mano and
metate shapes found at La Libertad can be attributed to style as well as function. The
different styles can be identified to different regions or villages or even different
20
manufacturers. According to Clark, modern users are able to distinguish artifact
attributes such as color, texture (or grain size of the stone), durability, as well as style.
Other important artifact attributes include hardness, overall size, weight, size and shape
of the grinding surface, and the number of usable grinding surfaces (Clark 1988:83-94).
Clark used the artifact attributes from his ethnographic observations when interpreting
the artifacts from prehispanic La Libertad. The attributes formed the basis of his
typological artifact groups. Clark’s study highlights the importance of recording the
various characteristics of grinding tools. From these characteristics, one can determine
function, style, and stone source.
Determining morphology, typology, function, and style can be useful in
discovering factors that influence choice of raw materials of maize-grinding tools and
help identify exchange patterns or different patterns of maize preparation in prehistoric
societies.
Source Analysis Studies
Source analysis is a way to link artifacts to their loci of origin. This connection
shows which sources ancient metateros used. From this knowledge, one can formulate
hypotheses of why one stone source may have been preferred over another.
Clark (1988) discovered that in La Libertad, the raw materials for making manos
and metates came from five different sources. He remarked that the stone with the lowest
density came from the furthest sources and those of the highest density came from the
closest sources. The apparent correlation between artifact density and distance traveled
led the author to conjecture that transportation was a factor in the choice of raw materials
21
for grinding tools at La Libertad in the Middle Formative (Clark 1988:131).
Spink (1984) used emission spectronomy analysis data and statistical analysis to
link metates to stone sources. Emission spectrometry yielded data for five major
elements and six trace elements. Her findings indicated that economic position, not
political or social position, determined the type of metate one would expect to find in a
Classic Period home in Copan. The larger, better quality metates belonged to people who
could afford them (Spink 1984:iii). Social relevance equated to material quality and
workmanship. In other words, “heavy, utilitarian items did not go far unless the elite
really wanted them” (Spink 1984:45). In other words, the needs of distant consumers
drove the distribution of these tools beyond their local origin. Spink’s study was an early
demonstration of the value of using source analysis of metates to answer questions about
prehistoric social and economic patterns.
Bostwick and Burton (1993) used attributes of raw material to source ground
stone tools from Hohokam sites of southwestern United States. The authors’ goal was to
find more basalt quarries in the Phoenix Basin and to identify the geographic distribution
of the quartz-basalt outside of the New River area. Their intent was to source the raw
material for ground stone tools in order to gain an understanding of Hohokam
manufacturing and exchange.
Although basalt is a limited resource in the Sonoran Desert, studies indicate it was
the preferred material for maize-grinding tools, especially metates. The team examined
fifty artifacts for mineral content using a dissecting microscope and back-scatteredelectron/energy dispersive x-ray microscopy. The microscopy process also provided
22
chemical data of the mineral content. They identified seven general attributes to aid
source identification: crystal inclusions, groundmass components, altered minerals,
secondary minerals, texture, color, and vesiculation. The authors determined that crystal
inclusions, altered and secondary minerals, and texture were the most diagnostic
attributes for identifying different sources (Bostwick and Burton 1993).
Results of the study indicate that quartz-bearing basalt was probably restricted to
the north side of the Salt River between the Westwing and McDowell Mountains.
Bostwick and Burton found four other basalt types that could have been quarried. They
also identified additional prehistoric quarries. Yet the study was unable to tell the
difference from New River and McDowell Mountain material (Bostwick and Burton
1993). This study demonstrates that various methods can be used to source raw materials
and what works best is a combination of methods. However, the authors assert that in
order to source artifacts, all major quarries must be identified and classified, and their
usage must be dated (Bostwick and Burton 1993:366).
The research in this thesis builds upon a foundation of earlier source analyses of
collections from Mexico (Biskowski 1997; Biskowski et al. 1999; Watson et al. 2006).
At the time Biskowski’s project began, a variety of research (Castañeda Saldaña 1976:7476; de Landero 1922; Sotomayor Castañeda 1968) documented petrographic differences
among the grinding tools and stone sources found in the Teotihuacan Valley. At that
time, no one had demonstrated the feasibility of utilizing data generated from Neutron
Activation Analysis (NAA) to differentiate among closely spaced stone sources within
this small region. Accordingly, some of the earliest work in his project examined local
23
stone sources. Altogether, during Biskowski’s initial work in the Teotihuacan Valley,
123 source samples from 22 sampling areas were submitted to NAA. Each sampling area
corresponds to an outcrop, a barranca, or a combination of adjacent barrancas, which
together form a meaningful zone for source collection. The NAA data from these
samples provided the basis for identifying 12 distinct chemical fingerprints. Five
additional fingerprints of unknown location were identified among the 328 samples of
Teotihuacan Valley grinding tools submitted to NAA (Biskowski 1997; Watson et al.
2006).
The substantive results of this initial research are summarized here to clarify the
importance of this current work. Grinding tools from early village sites prior to the rise
of Teotihuacan were the product of a small but skilled industry, which Biskowski argued
focused on a narrow range of lower valley stone sources. These Late Formative to Early
Terminal Formative metates are very well-made and apparently come from nearby
sources (Biskowski et al. 1999; Watson et al. 2006).
The most important collection from the next period, the Late Terminal Formative
Period, is from the fill of the Pyramid of Quetzalcoatl (Cabrera Castro et al. 1991;
Sugiyama 1993). These artifacts provide our best source of information about the
grinding tool industry during the economic transformation that accompanied the rapid
urbanization of Teotihuacan. Biskowski and others (1999) argue that the rapid influx of
population was followed by a collapse of the earlier lower valley industry accompanied
by a shift in production closer to the city in the middle valley. The metates that were
being produced at lower valley sources are among the most crudely made in the entire
24
Teotihuacan Valley sequence. However, the metates produced from the middle valley
sources are virtually identical to those encountered in later Classic Period contexts.
Within the Classic Period city, grinding tools from three apartment compounds
were produced at the same combination of stone sources. This result is consistent with
their exchange through the same mechanism, most likely the city market. Outside the
city, rural sites on the northern slope of Cerro Gordo have the same pattern of stone
usage. However, at Maquixco Bajo (Sanders et al. 1979), just 2 kilometers west of the
city, the inhabitants used a distinctive turtleback metate made from a source of unusually
dense stone, unlike any found at any other Teotihuacan Valley site up to this point in
time. Although the origin of this raw material is still unknown, it is clear that the people
of Maquixco Bajo obtained their grinding tools through a different exchange system than
did their urban contemporaries. Later, Aztec Period grinding tools may have been
exchanged via a combination of local reciprocity among established lineages and market
exchange within larger centers like Otumba (Watson et al. 2006).
Raw Material Selection
Using a combination of various source analyses and artifact attribute analyses can
provide a means to understand raw material selection in prehispanic societies. One focus
of Scott Cook’s (1982) ethnographic study of the Zapotec stoneworkers consists of how
the metateros (metate makers) chose raw materials. Metateros focused on color, texture,
and durability. First-class stones, those with grinding surfaces that last longer, are bluegreen or brownish. These are the most expensive because they are hard to find and
difficult to work with. Tools from second-class stone, green or purplish, are more
25
common because the stone is easier to find and easier to work. White stone is third class
stone and consumers believe tools made from this stone are not durable. Although
consumers consider the same factors of color, texture, and durability when purchasing
grinding tools, they will often buy second class grinding tools believing them to be first
class tools (Cook 1982).
Hayden (1987c) noted, in Guatemala, two conflicting ideals regarding raw
material preference for metates. Users wanted stone that was more durable because
metates would last longer. They preferred vesicular basalt to andesite. Users would
rather have stone tools made from a basalt that they called “black” stone to a type they
called “white” stone. The metatero preferred to work with less durable stone because it is
easier. He classified stone into four types identified by color: greenish and bluish (both
last about 15 years), a black that lasts 20 years, and an even blacker stone that lasts 30
years (Hayden 1987c). Again, the more durable the raw material, the longer lasting the
metate but the harder it is for the manufacturer to make the tool.
In a study of Homol’ovi III ground stone tools, Fratt and Biancaniello (1993)
show how different types of cement in sandstone affect use and raw material selection.
Homol’ovi III, located in Arizona, had two occupations: one dating to the late 1200’s and
the other in the early to mid 1300’s. The authors examined grinding tools from two types
of sandstone: Shinarump and Moenkopi. The study sample was small (n=200) because
burnt tools were excluded. Burning alters the appearance of stone and therefore can
cause errors in identification (Fratt and Biancaniello 1993).
The authors used several attributes to differentiate tools made of Shinarump from
26
those made of Moenkopi: color, bedding, tabularity, grain size, and sorting of grain size.
They noted that 80% of the manos, metates, and handstones consisted of Shinarump
sandstone and 80% of the grinding slabs consisted of Moenkopi sandstone. Data showed
an association between artifact type and sandstone type, suggesting two types of
sandstone performed differently (Fratt and Biancaniello 1993).
Fratt and Biancaniello discovered that the factors that influenced choice of
sandstone for grinding tools in Homol’ovi III are: how hard the stone is, how tight the
cement holds the sand grains together, how much sharpening a tool can take, and how a
tool looks. This suggests that the people of Homol’ovi knew the capabilities of the
different types of sandstone and where they could find each type. Although they used
local materials over non-local, there are indications that the people experimented
occasionally with non-local materials (Fratt and Biancaniello 1993). Again, although not
Mesoamerican in nature, the Fratt and Biancaniello study demonstrates the validity of
determining what factors influence choice of raw materials for grinding stones in
prehistoric societies.
Other Relevant Studies
Hayden’s work in Guatemala is critical to almost any study of maize-grinding
tools in Mesoamerica. Hayden (1987b, 1987c) focused on the manufacturing process of
metates as well as the use, curation, and replacement of stone tools to make metates. His
goals (1987c) for his study of using stone tools to manufacture metates were:
(1) to gather data concerning which material properties of stone makers and
users consider important,
27
(2) to determine stone tool efficiency by detailing stone tool usage and
performing time/motion studies,
(3) to document how stone tool shapes changed through use and resharpening,
(4) to discover the processes for site formation and waste deposition,
(5) to determine mano and metate market and distribution economies,
(6) to learn the social and economic position of metateros, and,
(7) to discover how resource scarcity impacts economic and social structures
(Hayden 1987c).
The author studied how metateros quarried, shaped, and finished metates; then he
did the same for manos. His results include rough estimates of how long each step took
and how long the entire process took, including search time needed to find suitable stone
material. Hayden then collected and analyzed data regarding the morphology and usewear of the various tools used to make metates and manos. It is important to note that the
tools’ name or identity stayed the same throughout the changing shape from usage, i.e., a
pic was still a pic regardless of the wear patterns. The use-wear study did not seem to
focus on the use-wear patterns of the metates themselves (Hayden 1987c).
In the broader archaeological context, it is not just important to know that metates
were made in a particular area in the past, but also to know if specialists manufactured
them, the quantity of manufacturing involved, whether grinding stone tools were
exported, and “what effect these higher-level behaviors had on local sociopolitical and
economic relationships” (Hayden 1987c:101). The author argues that, in certain cases, a
key factor for social stratification could be the restricted locations of important resources.
28
To explain his model, Hayden described variables that affect the role of “highly
localized important resources” and how they interact. The variables include how
localized the resource is; population density of the immediate area, the neighboring areas,
and the regional areas; and demand for the resource. They interact in four ways. Very
low demand, such as low population density, would not likely lead to social stratification.
Moderate demand coupled with moderate population of the surrounding area could lead
to local population monopolization of the nearby resource allowing those who are able to
control the resource to gain wealth and power. Moderate resource demand with low
potential local agriculture and much higher potential neighboring agriculture will
generate social stratification in the community that controls the important resource.
Moderate to high resource demand coupled with a high population regional center and a
low population local area will result in the regional center taking away control of the
important resource from the local population area (Hayden 1987c).
Hayden based his model on two assumptions. The first is that an early social
stratification system will spread to surrounding communities. The second is that armed
conflict can occur when there is direct competition for an important resource or if there is
a large possibility of economic loss or gain (Hayden 1987c).
In conclusion, Hayden suggested that his study should be considered exploratory.
He recommended that archaeologists should receive material science training. Knowing
why modern stone tool users choose particular materials and why they choose particular
sharpening strategies can open up “new dimensions in our understanding of past cultural
behavior” (Hayden 1987c:111).
29
In another study, Hayden (1987b) used ethnoarchaeological data to interpret uses,
curation, and stylistic replacement of prehistoric flaked and ground stone tools. He
examined the use of metal cutting tools in contemporary Maya societies to infer uses of
stone tools since subsistence patterns have not changed much over the years.
Most of the grinding tools in Chanal were nonvesicular andesite and most from
San Mateo were of vesicular basalt. Commercial metates in these areas are three-legged
and do not vary in morphological features. Observations in some households suggest that
the metates have many uses other than just grinding corn. However, these metates have
different sizes and shapes. People often reuse their broken manos and metates.
Hayden suggested that archaeologists can use use-life of grinding tools to
estimate length of site occupation. After commenting that, in general, the life span of
grinding tools is around 20 to 40 years, he observed that the tools vary from location to
location. The types of raw material, the number of extra grinding tools in the home, and
the maize requirements of the household also affect use-life. Each village has different
characteristics. He attributed some of the variation to style yet gives no explanation to
support this statement.
Other grinding implements that Hayden discussed were bax, or calcite, grinders
and manos. These tools also vary geographically. The bax-grinding manos vary more
than metates and are shorter than maize-grinding manos. This suggests that some early
grinding stones may have been for bax and not maize. Additional modern uses for
grinding tools were coffee, cacao, spice, salt, and sugar blocks. Unshaped stone tools
were used for pounding soap root, washing clothes, pounding herbs, husking grain,
30
grinding pigments, sharpening cutting tools, and smoothing pottery (Hayden 1987b).
Hayden explained how curation and storage affects the archaeological record. He
attempted to apply Binford’s (1980) suggested concept of curation to Highland Maya
villages. The villages are logistic (base residences with special procurement sites) and
almost all artifacts are curated. The author proposed three reasons why certain tools
would not be discarded at the site where they were used. Breakage or loss during
transport affects the presence/absence characteristics of artifact assemblages at a site,
since the expected artifacts would not be at the site. During storage, breakage or loss
would occur more often with fragile or smaller objects than with larger stone objects.
Additionally, “utilitarian objects do not enter archaeological contexts at sites where they
are not used” (Hayden 1987b:216). Thirdly, items that need to be repaired are often
brought back to residences or specialized centers. These three activities seem to
contradict Binford’s expected patterns (Hayden 1987b).
Recycling also has an effect on the archaeological record. Recycling is related to
curation in that the artifacts tend to be highly valued or may be of rare material, such as
metal. The perception of the usability of pieces after breakage determines the
recyclability of the object (Hayden 1987b).
In summation, higher sedentism probably led to using tools with longer lifespans
(Hayden 1987b). A higher investment in tools encourages recycling and repair at base
sites. This works for all artifacts regardless of material. As for replacement rates, those
households that have many industrial items also have many tradition items. Therefore,
archaeologists should look for positive correlations to infer traditional functional usage of
31
artifacts. Stone tool research can have “enormous potential for helping us to understand
prehistoric tool functions and processes affecting the creation of prehistoric and historic
lithic assemblages in the area, and probably in the other areas at comparable levels of
cultural development” (Hayden 1987b:229).
Horsfall (1987) used design theory to tie variations in grinding stones to cultural
processes and economic importance. Design theory is centered in design analysis.
Design analysis is defined as “a means of creating or adapting the forms of physical
objects to meet functional needs within the context of known materials, technology, and
social and economic conditions” (Horsfall 1987:333). Since design analysis is concerned
with the process of design, Horsfall used it as the foundation of her theoretical model.
Design theory fundamentally assumes that one makes an artifact in order to solve a
problem. It operationally assumes is that a “number of constraints operate on the
production and final form of artifacts” (Horsfall 1987:334). Choices are made when
constraints conflict resulting in a system of priorities. There are two types of change in
design theory; either change the tool to better solve the problem or change the problem.
Design theory resembles decision theory in that one chooses between alternatives but
differs in that design theory does not assume that humans know all options and
consequences of those options.
To develop the model, Horsfall studied the relationship between the production
and use of grinding stones and their context. By context, the author is referring to where
the tools reside within the study area, be it in the house or outside the house. Horsfall
determined that the constraints on the design process should fall under three categories:
32
functional, technological, and socioeconomic organization. These categories are applied
to the types of constraints: selection of material, morphology, and number and location.
The study compared artifacts from San Mateo and Aguacatenango, two towns in
Guatemala. Horsfall focused on any apparent diseconomies caused by conflicts in
constraints (Horsfall 1987).
Although limestone is plentiful in San Mateo, 83% of the sample is of imported
vesicular basalt, which indicates a diseconomy of time and energy. The functional
constraints on material selection are the material to be ground, the fineness of the grind,
and the use life of the different types of stone. Amount of grit does not seem to be a
major characteristic. For grinding stones, texture is one of the most important material
characteristics. Roughness of the grinding surface is also critical. Therefore, grinding
surfaces need to be resharpened, which makes resharpening frequencies significant.
Variation in stone texture controls the fineness of the grind. Fineness can have
social implications, such as white breads being indicative of high status in ancient Rome.
Fineness also influences cooking times and evenness. Evenness can reflect what is
cooked and times can reflect fuel usage.
Use-life is defined as the “length of time an artifact will last under specified
conditions” (Horsfall 1987:342). Grinding stone users prefer longer lasting “black”
stones while producers prefer “white” stones because they are easier to work (more about
this later). Grain size and grain-bonding are both important to use-life as they both affect
durability (Horsfall 1987).
Maize-grinding stones are more critical than non-maize-grinding stones. For this
33
reason, and the characteristics just outlined, people can justify purchasing imported
vesicular basalt metates. Special purpose grinding stones (non-maize) are made from
local materials, have a short use-life, and are not often found in houses. Their role in the
economy is small.
Technological constraints on material selection come from the perspective of the
manufacturer who seeks raw materials that are easily workable, resistance to breakage,
and less injurious to the hands. Resistance to breakage is the most important
characteristic because metateros do not want to lose time and income on a tool that never
makes it to market. These characteristics make the “white” stone preferable to the
“black” stone for producers, thus there is a conflict between functional and technological
constraints. The socioeconomic constraints are based on how much grinding needs to be
done, how important is grinding economically, the existence of a regional market system,
and the existence of craft specialization.
The shapes of grinding stones can also be separated by functional, technological,
and socioeconomic constraints. Functional constraints consist of what is being ground,
how much is being ground, controlling spillage from the metate, and, most importantly,
human energetic efficiency. Technological constraints include production tool
availability and stone cutting expertise. Socioeconomic constraints affect morphology
the most and include the following: importance of costs in energy of the users, existence
of a regional market system, existence of craft specialization, display of items indicating
social status, and importance of grinding to subsistence. A key point is that differences in
shape do not necessarily translate into differences in function (Horsfall 1987).
34
There are also constraints based on the location and frequency of grinding stones.
The functional constraints are expressed by having a convenient location for people who
frequently use the stones. Socioeconomic constraints encompass the economies of the
households and degree of involvement in regional economies. Ideological constraints are
based on traditional worldviews. Other considerations, in the modern context, include
use (or not) of metal corn grinders and motor-driven mills. In essence, neither the metal
grinders nor the mills grind the corn as fine as metates. Motor-driven mills can cost more
but reduce time expenditure. Metal grinders are faster than metates but cheaper than
mills. Usage of either is based on amount of integration into an extra-community
communication and interaction. Modern technology’s primary impact is the “addition of
a supplementary technology to reduce the time and energy spent on grinding” (Horsfall
1987:368). The contrasts between San Mateo and Aguacatenango suggest the possibility
that earlier cultures may have had a greater variety of specialized grinding tools (Horsfall
1987).
Horsfall summarizes the study with five points:
(1) Traditional contexts have variations in grinding functions.
(2) Material variation is tightly coupled to functional variation.
(3) Multiple morphological variations solve the same functional problem.
(4) The logic behind the number and placement of grinding stones varies with
the cultural context. This point also holds for the transformation to the
archaeological context.
(5) Acculturation affects material inventory which results in decreased
35
variation in function and technology (Horsfall 1987:369-370).
The author finished with three recommendations. First, pay more attention to
grinding stones since they can provide a lot of information about subsistence behavior,
social implications, and possibly even forces for cultural evolution. Second, be more
attentive to physical properties of artifacts. Third, use design theory more often since it
has the “potential for unifying multiple levels of analysis and interpretation” (Horsfall
1987:372).
These selected studies provide a basis and background for this thesis. This work
uses artifact attribute analysis, geochemical analysis, and source analysis to identify three
factors that influenced stone selection for manos and metates in prehistoric Mexico.
Regional Prehistory and Grinding Tool Analyses within Each Region
The next sections detail research from the Apizaco region of Tlaxcala, the
Teotihuacan Valley, and the Tula region in the Mezquital Valley. These areas provided
the collections for this research.
Apizaco
The Apizaco study region is located in the north-central part of the state of
Tlaxcala, which is the smallest state in Mexico. The study region includes the upper
Zahuapan river drainage, the northwestern slopes of La Malinche, and the Apizaco Basin
(Lesure et al. 2006). Farming has heavily eroded the land over the last 3000 years
(Borejsza et al. 2008).
This thesis focuses on collections from four Formative period sites in Apizaco:
Amomoloc, Tetel, La Laguna, and Las Mesitas. The sites were located and dated as part
36
of extensive surveys by Snow and García Cook (García Cook 1981; Snow 1969). They
were the only Formative sites that could still be excavated and could provide information
about the development of the area. Lesure and others excavated the sites as part of a
project designed to investigate agricultural origins and land-use history of Tlaxcala
(Borejsza 2006; Borejsza et al. 2008; Lesure 2007; Lesure et al. 2006). La Laguna was
chosen because it is the largest Formative site and had ceremonial architecture (Carballo
2005; García Cook 1981; Lesure et al. 2006; Snow 1969). Tetel and Amomoloc were
selected for investigation because they were the earliest Formative sites (Lesure et al.
2006).
The Amomoloc site dates to the Middle Formative about 900-600 BC
(Tzompantepec and Tlatempa phases). Tetel is a Middle/Late Formative site dating to
about 700-400 BC (Tlatempa and Texoloc phases). Las Mesitas has a Late/Terminal
Formative occupation of about 500-350 BC (Texoloc phase). La Laguna has two
occupations. The first occupation dates to about 600-400 BC (Texoloc/Tezoquipan
phases). The site was deserted from 400 BC to 100 BC. The second occupation was in
the Preclassic Period and dates to about 100 BC to AD 100. However, since the manos
and metates from La Laguna used for this study come from the earlier occupation, the
second occupation will not be mentioned further. This puts Las Mesitas as the latest site.
Changes in dating of the La Laguna artifacts could alter analysis results and conclusions
made in this thesis.
Tlaxcala participated in several exchange networks from various trade corridors
(Carballo et al. 2007; Carballo and Pluckhahn 2007). Carballo and Pluckhahn used
37
settlement pattern studies in suggesting the existence of trade corridors for obsidian. The
extent of exchange and trading partners changed over time. Although evidence for
exchange between Tlachinolpan and the Tlaxcala area is indicated, there does not seem to
be any evidence for a market place (Lesure et al. 2006). The exchange system may
represent localized mechanisms of exchange, possibly kin-centered mechanisms of
reciprocal exchange (Biskowski et al. 1999). This corresponds nicely with the nonmarket place-based exchange operational chain (Watson 2007). The results of the study
by Carballo and his team “support a sociopolitical reconstruction in which the villages
and early regional centers of Tlaxcala-Puebla became increasingly interconnected with
the Basin of Mexico economic sphere during the Middle to Late Formative periods”
(Carballo et al. 2007:29). Carballo’s work focused on obsidian exchange, not on the
movement of maize-grinding tools. Evidence indicates that exchange patterns of
grinding tools did not necessarily match those of obsidian or other goods (Biskowski et
al. 1999; Watson et al. 2006).
Tlachinolpan
Tlachinolpan is located about halfway up the northeast side of Cerro Malinalco in
the Teotihuacan Valley. The polity would have been on the extreme northwest of
Patlachique Phase Teotihuacan. The site covers about 7.3 hectares and was first settled
about 300 BC. It was abandoned in the late Tzacualli Phase or somewhere between AD 1
and AD 100. Excavated by Darlena K. Blucher, the purpose was to “investigate the
problem of Teotihuacan’s origins” (Blucher 1971:415).
38
In the beginning, Tlachinolpan was a small agricultural community and was
probably politically autonomous. Evidence indicates the site had contact with Tezoyuca
in the lower Teotihuacan Valley and possibly with locations outside the Valley of
Mexico. Figurines suggest continued contact with Tezoyuca into the early Patlachique
Phase, about 100BC. The actual size of Tlachinolpan at this time period is unknown. By
the late Patlachique Phase, Tlachinolpan was part of Teotihuacan (Blucher 1971).
Some Tlachinolpan buildings differ from all other buildings elsewhere in the
Teotihuacan Valley. Based on evidence, the buildings are not domestic but probably not
religious in nature. Therefore, Blucher interpreted the buildings as civic or public
buildings and the site as a whole as an administrative center. There was no evidence of
any kind of workshop at the site. The site was abandoned just before the Classic Period.
Tlachinolpan seemed to be a logical base for the growth of Tzacualli Phase Teotihuacan
(Blucher 1971).
Martin Biskowski studied the maize-grinding tools from this site (Biskowski et al.
1999; Biskowski and Watson 2007; Watson et al. 2006). Using artifact attribute analysis,
Biskowski found that the Tlachinolpan metates were unusually well made. Over 90% of
the 60 artifacts had evidence of supports or feet. Contemporaneous lower Teotihuacan
Valley sites, such as Cuanalan, Tezoyuca, and Venta de Carpio (Sanders et al. 1975), also
had well-made metates (Biskowski et al. 1999). Further research and comparisons to the
Apizaco collection suggested that Tlachinolpan shows the same general pattern of maize
preparation intensification as Apizaco during the same time period or slightly later
(Biskowski and Watson 2007). NAA suggests some evidence of exchange with the
39
Apizaco region early in Tlachinolpan’s career (Watson et al. 2006). Further study of this
collection could provide a clearer picture of what was going on between these two areas
before the rise of Teotihuacan.
Mezquital Valley
The Mezquital Valley is located in the state of Hidalgo and is the home of the
Toltec civilization. The capital city, Tula or Tollán, is located about 70 kilometers north
of Mexico City and overlooks the Tula and Rosas River valleys. It covers about 10.5 to
14 kilometers squared. Archaeologists date the city between AD 900 and AD 1200,
although it was probably settled around the time of the collapse of Teotihuacan (Healan
1977). Two areas were excavated as part of a project by the University of Missouri under
the direction of Richard Diehl. One set of excavations, the Canal Excavations, focused
on living spaces of the non-elite (Healan 1977). A second area, called El Corral and
located only 50 meters from a temple, was excavated with the intent of discovering
information regarding elite households (Mandeville and Healan 1989). The excavations
here provided the collection of grinding stones that Stroh analyzed (Stroh 1975).
Stroh’s work in Postclassic Tula (Stroh 1975) was one of the first attempts to
identify room function based on the location of maize-grinding tools. Room function can
be used in providing information for economy, social organization, and residential
patterning (Stroh 1975:2). Stroh attempted to identify kitchens based on the distribution
of stone grinding implements in areas where hearths are not obviously present. His
hypothesis was based on the assumption that food preparation artifacts would more likely
be found together than tools not used for food preparation. From his distributional
40
analysis of manos, metates, and other ground stone tools from Postclassic Tula, Stroh was
able to identify several rooms as definite kitchens by comparing observed frequencies of
tools and hearths by grid unit to those predicted by the Poisson distribution. Other rooms
that lacked hearths were only tentatively identified as kitchens (Stroh 1975:37-40). His
work supports the idea that one can identify kitchens from the location of maize-grinding
tools with only probable evidence of a hearth (Stroh 1975:36).
Tula had a highly organized market system (Diehl 1983:113). Healan suggests
there is evidence for tribute-based long distance exchange of obsidian blades (Healan
1993). Fournier and Chávez (2000) list many imports, none of which include raw
material for grinding tools or the tools themselves. According to Diehl, the average
Toltec family met their materials needs locally while the elite used imported products.
“[T]he central Mexican heartland provided the Toltecs with virtually all the basic
resources they needed. Foodstuffs, fibers, obsidian, basalt, construction materials, wood,
lime, and other necessities were available in quantity within a three or four day walk from
Tula” (Diehl 1983:138). Based on these observations it would appear that maizegrinding tools were exchanged only locally. Source data obtained from NAA tentatively
support this conclusion (Watson et al. 2006). What is not clear is whether the grinding
tools were exchanged via the market place. It is possible that the market place was
strictly for long-distance trade. However, Tula, during its maximum occupation,
numbered roughly between 40,000 and 60,000 with another 60,000 in the surrounding
area (Healan 1989:245). Thus, it would seem likely that local market places were used as
41
well as kin-based forms of exchange. This suggests that probably two operational chains
of exchange were in effect here (Watson 2007).
The Mezquital Valley collection used in this thesis came from excavations of
several Classic and Epiclassic sites done by Fournier and others (Fournier 2001; Fournier
and Bolaños 2000, 2007; Fournier and Chavez 2000; Fournier and Pastrana 1999). The
goal of Fournier’s work was to understand the sociopolitical development, economic
development, and ideological changes of the Tula region during the Epiclassic Period.
Some of the artifacts come from the site of Chapantongo. Chapantongo was occupied
from about AD 650 to AD 950 and contemporary with Tula Chico, which is less than 27
km to the south. The site is about 2.5 square kilometers and may have had a population
of about 6000 at its height. Most of the artifacts come from excavations of elite
residences and burials.
Chapantongo may be critical to comprehending the social, cultural, and religious
changes that occurred in northern Mesoamerica and the end of the Epiclassic. It is still
not known if the area was independent or subservient to Tula Chico. Evidence indicates
that both sites had equal access to trade goods and had the same ceramic traditions. One
critical difference is that no one has discovered a ball court in Chapantongo, possibly
because it was covered or destroyed by either colonial or modern Tula. It is also possible
that it never had a ball court since Chapantongo does not have abundant evidence of
social distinctions or rulership. Evidence indicates that by the end of the Epiclassic,
Chapantongo was reduced to a hamlet, Tula Chico was abandoned, and Tula Grande
began to assume control of the region (Fournier and Bolaños 2007).
42
Chapter 3
METHODS OF ANALYSIS
I used artifact attribute analysis and geochemical analysis to investigate factors
that influenced choice of raw material in the manufacture and usage of maize-grinding
tools. Using artifact attribute analysis, I was unable to demonstrate clearly whether
durability was a factor in the Apizaco region or in the Mezquital Valley. However, using
geochemical analysis, I concluded that design type was critical for selecting material for
grinding tools in the Apizaco region. Data from a macroscopic geological examination
provided more evidence to support my conclusion. Results from geochemical analysis
supplied evidence indicating that Tlachinolpan was not restricted to using nearby middle
Teotihuacan Valley stone sources for grinding tools. These two types of analysis will be
discussed in the next sections of this chapter.
Artifact Attribute Analysis
Artifact attribute analysis is the process of examining the characteristics of
artifacts in order to make meaningful statements about them. The data I used were
captured in a format originally designed by George Cowgill to analyze the grinding tools
from the Teotihuacan Mapping Project. Martin Biskowski (1997) expanded the format in
a subsequent study of Teotihuacan Valley grinding tools. Examples of the data sheets
used to collect the artifact attribute information are located in Appendices E, F, and G.
Much of the artifact attribute information had been acquired by a previous project
(Gueyger and Biskowski 2005).
43
Artifact attribute analysis of the manos and metates in the collections can
demonstrate a preference for certain raw materials by comparing the number of artifacts
that have similar characteristics with the number of dissimilar artifacts. These analyses
can also yield important information on actual usage and intended function. For
example:
“The size and shape of the grinding surface will limit how much plant
matter can be processed at one time. The concavity of the grinding
surface will determine how well plant matter remains on the metate
during grinding as well as the amount of pressure that can be brought
to bear during grinding. The shaping of the ventral surface will affect
the stability of the metate if it is not otherwise supported. The
presence of “feet,” or supports, on the ventral surface may stabilize the
metate and can also alter the angle of the grinding surface.” (Gueyger
and Biskowski 2005:4-5)
I used artifact attribute analysis to see if I could measure durability in Apizaco
manos and metates. Hayden (1987a) stated that durability in vesicular basalts is related
to high density, small vesicle size, and a low number of vesicles. Modern users preferred
metates made from basalt that had fewer vesicles because those metates last longer.
Artifacts from dense basalt were harder to work but lasted longer (Hayden 1987a). If
durability was a factor in choosing raw material for maize-grinding tools in Apizaco and
is measurable by the above three artifact attributes, I expect to see many artifacts with
high density, fine or no pores, and granular texture quality.
Although there are several direct ways to calculate durability, I did not have
access to the necessary equipment (Los Angeles abrasion procedure and a hydraulic ram)
and had no way to perform impact tests on the artifacts. Therefore, I based my
conclusions on the analysis of artifact attribute data. I chose density, porosity, and
44
texture quality as the closest matches to Hayden’s characteristics from the artifact
attribute data sheets to which I had access. Density equals mass divided by volume,
which I measured in grams per milliliter. Porosity and texture quality are similar to
Hayden’s attributes of vesicle size and number of vesicles. Porosity, or coarseness, was
estimated on an ordinal scale of 0 to 5, zero equating to no pores and 5 being very porous.
I measured texture quality, or granularity, by looking at the quantity of vesicles. Texture
quality was measured on a scale of 0 to 2, 0 being vesicular or lots of vesicles, 1 being
vesicular/granular, and 2 being granular or few to no vesicles. Density, porosity, and
texture quality are important characteristics because they determine how strong a
particular stone will be. After identifying which attributes might measure durability, I
used the SAS statistical analysis software package version 9.1 frequency program and
MS Excel 2003 to calculate frequencies, percentages, and averages (means) (Biskowski
1997).
Most basalts should have a density value between 1.8 and 2.6 (Martin Biskowski,
personal communication 2009). Some artifacts in the collections had an impossibly high
density value. Several other artifacts had density values that were too low. Possibly,
these unusual values result from errors in calculating the mass, or the volume, or both.
The errors could also be due to the size of the artifact because smaller artifacts have more
variance both above and below normal values. Because the artifacts are located in
Mexico, I could not re-examine the artifacts to make any corrections. Hence, the
frequency calculation program filtered out artifacts that had density values greater than 3
and less than 1.8, a range which would include as many artifacts as possible.
45
Appendix A contains the density, porosity, and texture quality data for the
Mezquital Valley manos. Appendix B contains the equivalent data for Mezquital Valley
metates. Since there were so many Mezquital Valley sites, in the interests of clarity, only
those sites with NAA data or more than one artifact were explicitly listed. Artifacts from
the remaining sites were grouped under ‘Other’. Apizaco mano density, porosity, and
texture quality data are in Appendix C and the Apizaco metate data are in Appendix D. I
discuss the results in Chapter Four. Use of other methods to calculate durability could
alter my conclusions.
Geochemical Analysis
I used two types of geochemical analysis data to identify factors influential in raw
material selection: NAA and a geological examination. I identified patterns by
highlighting the similarities and differences in the various materials used.
Neutron Activation Analysis (NAA)
Stone sources were investigated using NAA in Tlachinolpan and the Apizaco
region. Stone source analysis can indentify factors of choice in two ways. First, it can
show a preference for one source over another when both are within the same distance of
a settlement. Second, it can show a preference for a raw material source that is located
farther away from a settlement over another source located much closer. However,
according to Schneider and LaPorta, “...geochemistry certainly plays an important part in
limiting the ‘field of play’ but it is not the definitive means of actually locating quarries
for basaltic vessels and milling implements...” (Schneider and LaPorta 2008:34).
46
The Apizaco and Tlachinolpan collections each contributed 40 samples for NAA
for a total of 80 artifacts. Individual artifacts for sampling were selected based on
diagnostic value of the artifacts, the representativeness of the functional and stylistic
attributes, and similar factors.
Sample Preparation
Samples submitted to NAA began as small (mostly 4g to 8g) pieces of stone cut
from the interior of an artifact using a lapidary saw. I took photos before cutting the
sample from the artifact to minimize any loss of information and made the cut from parts
of the artifact that would not detract from any diagnostic information. The cut samples
were placed in bags with identification tags and then exported from Mexico to the
laboratory at California State University, Sacramento (CSUS). In the lab, I pulverized
the small pieces into powder using two steps. After inserting the cut piece of stone into a
Plattner stainless steel diamond mortar with a 30mm aperture, I drove a flat-topped pestle
downward with blows from a sledgehammer in order to crush the stone. Then, I
transferred the resulting small bits to a small (70mm aperture) alumina mortar and ground
them into powder. Afterwards, I put the powder into plastic vials using a plastic funnel.
The plastic vials were sent to the Missouri University Research Reactor facility (MURR)
for submission to long irradiation NAA. I washed the tools, rinsed them with distilled
water, and let them dry after each sample to reduce any contamination between artifacts.
I dried the tools using an equipment-drying oven before pulverizing the next stone piece
(Figure 2).
47
Figure 2. Drying oven with mortars and pestles. Photos by Cristi Hunter.
Statistical Analysis
The resultant geochemical data were parts-per-million counts of 33 chemical
elements. I log-transformed and then analyzed the data using procedures outlined by
Glascock (1992). The analyses were implemented in a system of programs made
available by MURR. These programs are based on Smithsonian Archaeometric Research
Collections and Records (SARCAR) as translated into the Gauss language by Hector
Neff and subsequently revised by Bill Grimm. I relied mostly on principal component
analysis (PCA) to accomplish dimensionality reduction (Read 1985). I also utilized
canonical discriminant analysis (CD) to explore the separability of different groups of
samples and hierarchical cluster analysis to delineate patterns within groups (cf. Read
1985).
48
Design or Metate Type
I examined the Apizaco, Tlaxcala collection to determine if the footed metates of
the Late Formative Period came from the same stone sources as slab metates of the
Middle Formative Period. I ran principal component analysis and hierarchical clustering,
using the SARCAR software previously mentioned, on the NAA data to classify artifacts
into related groups. Appendix H contains the principal component analysis scores and
the hierarchical clustering diagram. Group numbers were sequentially assigned to
brackets in the hierarchical clustering diagram. I verified the contents of each group with
data from a macroscopic geological examination performed by Jessica Jones, who was an
undergraduate with a geology background at CSUS at the time. She used a Hamilton
Bell x10 hand lens to perform the examination. The geological examination identified
the rock type, color, texture, condition of the artifact where the examination was
performed, oxidation, mineral content, and any other features that might be important.
After deciding which grinding tools belonged to each group, I took photos of the groups.
Then I identified what kind of artifact was in each group and the artifact’s associated time
period. Based on this process I was able to group artifacts that most likely shared a raw
material source. See Chapter Four for the results.
Tlachinolpan Stone Sources
As stated in Chapter One, I determined that the site of Tlachinolpan was not
restricted to using nearby middle Teotihuacan Valley stone sources for their manos and
metates. To do this I performed a series of statistical analyses, again using SARCAR
49
software, on the NAA data to determine raw material sources as explained in the next
paragraphs. I used the same source fingerprints that Biskowski (1997) used to determine
the source assignments in Teotihuacan Valley (Figure 3 and Figure 4).
Figure 3. Teotihuacan Valley sites and fingerprint source sampling areas (Biskowski, et al. 1999;
Watson, et al. 2006). Map created by Martin Biskowski.
50
Figure 4. Teotihuacan Valley source fingerprints (Log Th vs. Log Cr).
NAA returned data for thirty-three chemical elements. In order to perform
comparisons, I had to restrict the number of chemical elements of the artifacts to the
twenty elements that Biskowski used for his analyses (Biskowski 1997). Biskowski
selected the twenty elements based on the samples that had the fewest number of zero
values.
Following Biskowski’s methodology, I split the fingerprints into high, medium,
and low chromium groups. I ran principal component analyses to calculate the axes with
each applicable chromium group of source fingerprints. I scored the artifact samples on
51
the principal component axes. I projected the scores against the source fingerprint data.
Then I estimated the probability that a particular artifact came from the same rock source
as the source fingerprint using Mahalanobis distance of each artifact sample to the
centroid of each fingerprint. Since the chromium groups overlap, there was the
possibility that analyses could assign artifacts to more than one source. I assigned
artifacts to the source with the highest probability of membership. The principal
component analysis data and probability calculation results are located in Appendix I.
Artifact assignments to particular sources are discussed in Chapter Four.
Summary
Artifact attribute analysis and geochemical analysis have been proven effective in
identifying factors that influence which raw materials will be used to make grinding tools
(Biskowski 1997; Biskowski et al. 1999; Biskowski and Watson 2008; Gueyger and
Biskowski 2005; Watson et al. 2006). However, as results in Chapter Four will show, it
was unclear whether the combined attributes of stone density, porosity, and texture
quality could provide a measure of durability in stone maize-grinding tools for the
Apizaco region and the Mezquital Valley. The results from the geochemical analysis are
more persuasive.
52
Chapter 4
RESULTS
This chapter examines which factors influenced ancient metateros’ decisions for
choosing stone for the manufacture of grinding tools. The first part of the chapter
discusses why one may not be able to measure the durability of basalt maize-grinding
tools from Apizaco or the Mezquital Valley by combining the attributes of stone density,
porosity, and texture. Changes in these three attributes over time and place can be
understood by examining tools from the Apizaco region and the Mezquital Valley, with
artifacts dating from several time periods. In the second part of this chapter, the results of
statistical analysis of stone geochemistry and a geophysical examination identify the
usage of different stone sources based on metate design type in Apizaco. Finally, data
analysis supports the assignment of some of the artifacts from Tlachinolpan to possible
stone sources within the Teotihuacan Valley and indications of source usage outside the
Teotihuacan Valley.
Factors Determined by Artifact Attribute Analysis
Durability
Durability of vesicular basalt maize-grinding tools in Guatemala is related to high
density, small vesicle size, and a low number of vesicles (Hayden 1987a). Therefore, if
durability was a factor in choosing raw material for maize-grinding tools in the Apizaco
region or the Mezquital Valley, many artifacts should share the following characteristics:
high density, fine or no pores, and granular texture quality. In addition, one would expect
53
to see an increase in high density, fine pored, granular textured manos and metates as
durability becomes more important through time.
Apizaco
In an earlier study regarding maize preparation intensification, Biskowski and
Watson (2007) noted that the porosity of Apizaco metates changed at the same time as
the introduction of footed metates. However, instead of using finer pored stone, which
one would expect with increased intensification of maize preparation, the stone was
coarser. The authors suggested that the change to more coarse stone for metates could be
related to durability. This is the opposite of one of the attributes of durable materials in
Guatemala. Results show that the relationship between artifact attributes and durability is
complicated. In addition, the low frequency of artifacts, especially from Las Mesitas,
could be obscuring the observed patterns.
The distribution of density for Apizaco metates and manos are given in box-andwhisker charts (Figure 5 and Figure 6). The box represents the range of density
measurements for 50% of the artifacts. The horizontal line inside the box represents the
median value for density. The top and the bottom of the vertical lines, called whiskers,
define the range of density measurements for the grinding tools studied.
54
Figure 5. Apizaco metate density frequencies g/ml.
Figure 6. Apizaco mano density frequencies g/ml.
55
There is no gradual trend toward the increased usage of dense stone for metates at
Apizaco. The pattern for stone density in metates shows a decrease in stone density over
time followed by an increase in stone density in the Late Formative. For metates, the
density range for Amomoloc is large (Figure 5). The range decreases at Tetel, increases
again at La Laguna, and is the smallest at Las Mesitas. The mean density for metates
drops from 2.32 g/ml during the Middle Formative period to 2.23 g/ml by the Late
Formative until it goes up again in the Late/Terminal Formative (2.36 g/ml) (Table 2).
Table 2. Apizaco Metates Stone Density g/ml. Apizaco Sites in Bold. Comparative Sites from Biskowski
(1997).
Period
MF
MF/LF
LF
LF/TF
LF
LF/TF
Classic
Classic
Context
Amomoloc
Tetel
La Laguna
Tlachinolpan
Pyramid of Quetzalcoatl
Las Mesitas
TMP
Maquixco Bajo
N
Obs
13
6
37
12
93
4
47
13
Min.
1.86
2.01
1.75
Max. Median
2.57
2.37
2.34
2.25
2.55
2.24
2.30
2.41
2.36
Mean
2.32
2.22
2.23
2.38
2.34
2.36
2.29
2.46
Std.
Dev.
.18
.13
.18
.05
The low number of metates at Las Mesitas and random chance could be obscuring
the expected pattern. Yet, comparisons to artifacts from Late/Terminal Formative
Tlachinolpan (mean density 2.38 g/ml) and the Pyramid of Quetzalcoatl (mean density
2.34 g/ml) (Table 2) indicate that the mean density for Las Mesitas metates is not
unusually high.
Manos also do not exhibit a gradual increase in density over time. For manos,
stone density does not change much. However, the density range is different at each site
56
(Figure 6). These differences are echoed in the artifact density means: 2.33 g/ml for
Amomoloc, 2.29 g/ml for Tetel, 2.34 g/ml for La Laguna, and 2.32 for Las Mesitas
(Table 3). Nevertheless, the manos’ median density remains relatively unchanged (2.35
g/ml) (Table 3).
Table 3. Apizaco Manos Stone Density g/ml.
Period
MF
MF/LF
LF
LF/TF
Context
N Obs
Amomoloc
28
Tetel
8
La Laguna
28
Las Mesitas
3
Min. Max. Median Mean Std. Dev.
1.97 2.62
2.36
2.33
.19
2.02 2.41
2.35
2.29
.14
1.98 2.58
2.35
2.34
.16
2.31 2.34
2.31
2.32
.02
No gradual trend exists toward using fine pored stone for Apizaco metates over
time. At Amomoloc, people used mostly fine or medium pored stone for their metates
with only a little usage of coarse stone (Figure 7). Tetel had mostly medium pored
metates and only a few coarse metates. Researchers found no fine pored metates at Tetel.
Usage of coarser stone for metates increased by the Late Formative at La Laguna.
However, there is also a large increase in the use of medium pored stone. At Las
Mesitas, none of the metates was made from coarse stone. Metates seem to exhibit an
increase in coarseness by the Late Formative (Table 4). Here it seems that the low
frequency of Las Mesitas metates could be affecting the expected trend. Comparisons
with both Late/Terminal Formative and Classic Teotihuacan sites suggest that the mean
porosity score of Las Mesitas metates seems to be too low (Table 4). However, any
movement in the low mean porosity score would most likely be toward the usage of more
coarse material leading further away from the predicted trend of fine pored tools.
57
Table 4. Apizaco Metates Mean Porosity Scores. Ordinal Scale of 0 to 5; 0 = No Pores and 5 = Very
Porous. Apizaco Sites in Bold. Comparative Sites from Biskowski (1997).
Period
MF
MF/TF
LF
LF/TF
LF
LF/TF
Classic
Classic
Context
Amomoloc
Tetel
La Laguna
Tlachinolpan
Pyramid of Quetzalcoatl
Las Mesitas
TMP
Maquixco Bajo
N Obs
13
6
37
12
93
4
47
13
Mean
2.54
3.17
3.11
3.75
3.20
2.25
3.49
2.62
Std. Dev.
.78
.41
.74
.50
25
20
Number of artifacts
20
15
Fine
Medium
Coarse
10
10
7
6
6
5
5
3
1
1
1
0
Amomoloc
Tetel
La Laguna
Las Mesitas
Site
Figure 7. Apizaco metate porosity frequencies.
Ancient peoples preferred fine pored manos about half of the time. Only half of
the manos from Amomoloc were made from fine pored stone (Figure 8). At Tetel, 50%
of the manos were medium pored. La Laguna distributions look almost identical to those
58
of Amomoloc. At Las Mesitas, none of the three manos came from fine pored stone.
The trend shows no change in the type of stone used for manos (Table 5). Again, the low
number of artifacts at Las Mesitas and random chance may be obscuring the expected
trend. This is especially evident when comparing the manos’ mean porosity scores
between Apizaco and Late Formative/Classic Teotihuacan Valley sites (Table 5). A
mean porosity score of 3.67 at Las Mesitas is much higher than any other site. Yet, the
mean porosity scores from contemporary Teotihuacan Valley sites support a trend toward
the use of coarser stone for manos, at least until the Classic Period when stone selection
patterns apparently shifted towards employing more finer textured stone.
16
14
14
14
Number of artifacts
12
10
Fine
Medium
Coarse
8
8
7
7
6
6
4
4
3
2
2
1
1
0
Amomoloc
Tetel
La Laguna
Las Mesitas
Site
Figure 8. Apizaco mano porosity frequencies.
59
Table 5. Apizaco Manos Mean Porosity Scores. Ordinal Scale of 0 to 5; 0 = No Pores and 5 = Very Porous.
Apizaco Sites in Bold. Comparative Sites from Biskowski (1997).
Period
MF
MF/LF
LF
LF
LF/TF
Late TF
LF/TF
Classic
Classic
Classic
Classic
Classic
Classic
Context
Amomoloc
Tetel
La Laguna
Cuanalan
Tlachinolpan
Venta de Carpio
Las Mesitas
TMP S3W1
TMP N1E4
TMP N6W3
Other TMP
N. Cerro Gordo
Maquixco Bajo
N Obs
28
8
28
3
31
4
3
15
16
34
296
14
11
Mean
2.46
2.75
2.71
3.33
3.35
3.25
3.67
2.67
2.31
2.94
2.75
3.21
2.55
Std. Dev.
1.43
.71
1.36
1.15
Finally, neither metates nor manos show a trend toward increased usage of
granular stone. Stone with medium vesicles predominates for metates throughout (Figure
9). Vesicular stone use increases from the Middle Formative at Amomoloc up to Late
Formative La Laguna then drops off by the Late/Terminal Formative at Las Mesitas.
Average texture quality scores for metates drop after the Middle Formative then increase
in the Late/Terminal Formative (Table 6). Again, the changes observed between the
Middle Formative and the Late/Terminal Formative may be due to a lack of data from
Las Mesitas (n=4). For manos, some granular stone is used at Amomoloc and La
Laguna, but not at Tetel or Las Mesitas (Figure 10). Medium textured stone
predominates for the manos at Amomoloc, La Laguna, and Las Mesitas. The exception
is at Tetel, where vesicular manos are the only kind present. The mean texture quality
scores for manos do not show usage of granular stone manos at all (Table 7).
60
25
22
Number of Artifacts
20
15
14
Vesicular
Medium
Granular
10
8
5
3
3
3
3
2
1
1
0
Amomoloc
Tetel
La Laguna
Las Mesitas
Site
Figure 9. Apizaco metate texture quality frequencies.
Table 6. Apizaco Metates Mean Texture Quality Scores. Ordinal scale of 0 to 2; 0 = Vesicular, 1 =
Medium, and 2 = Granular.
Period
MF
MF/LF
LF
LF/TF
Context
Amomoloc
Tetel
La Laguna
Las Mesitas
N Obs
13
6
37
4
Mean
1.08
.50
.65
1.25
Std. Dev.
.64
.55
.54
0.50
61
20
18
18
16
15
Number of artifacts
14
12
Vesicular
Medium
Granular
10
8
8
8
6
6
5
4
4
2
2
1
0
Amomoloc
Tetel
La Laguna
Las Mesitas
Site
Figure 10. Apizaco mano texture quality frequencies.
Table 7. Apizaco Manos Mean Texture Quality Scores. Ordinal scale of 0 to 2; 0 = Vesicular, 1 = Medium,
and 2 = Granular.
Period
MF
MF/LF
LF
LF/TF
Context
Amomoloc
Tetel
La Laguna
Las Mesitas
N Obs
28
8
28
3
Mean
1.11
0
1.07
.67
Std. Dev.
.69
0
.60
.58
To summarize, metates at Amomoloc were often of dense, non-coarse, nonvesicular stone and the manos were often of dense, fine pored, non-vesicular stone. Tetel
metates were not as dense, much less fine pored, and more vesicular while the manos
were dense, vesicular stone with a variety of porosity. Similarities in Tetel stone
attributes suggest that Tetel artifacts all came from the same material; the difference in
porosity may just indicate variants of the same stone source. It warrants mentioning that
62
Tetel is located near a basalt source and could be a quarry site (David Carballo, personal
communication 2011). Metates from a single, conveniently nearby quarry would more
likely have similar attributes. People at Late Formative La Laguna used more medium
dense, medium pored, medium vesicle stone for their metates and more fine pored stone
for their manos. However, many of the manos at La Laguna are fine pored with medium
vesicles. The opposite stone usage pattern obtains at Las Mesitas, a Late/Terminal
Formative site. People at Las Mesitas used mostly fine stone for their metates and
coarse, vesicular stone for their manos.
In conclusion, for Apizaco, if metate-makers and users required more durable
tools as maize preparation intensified, the requirement does not seem to be reflected in a
trend toward denser, finer pored, granular stone. A trend toward that type of material is
not apparent for either Apizaco manos or metates. Yet, some important patterns have
emerged from the data. First, Apizaco metate density decreases from the Middle
Formative through the Late Formative periods (Table 8). Second, the use of coarse stone
for metates increases from the Middle Formative through the Late Formative periods
(Table 8). Third, the use of vesicular stone for metates increases from the Middle
Formative through the Late Formative periods (Table 8). The changes observed in these
patterns in the Late/Terminal Formative could be real or a statistical anomaly, since there
are so few metates from Las Mesitas. If real, then the changes in stone usage patterns
could be related to the changes occurring in Late/Terminal Formative Teotihuacan.
Manos exhibit a different pattern (Table 9). Mano density remains consistent over time.
63
Stone coarseness for manos increases over time. In addition, except for Tetel, stone
granularity in manos stays relatively unchanged.
Table 8. Summary of Apizaco Metate Attribute Means.
Middle
Middle/Late
Late
Late/Terminal
Attribute Formative Formative Formative
Formative
Density
2.32
2.22
2.23
2.36
Porosity
2.54
3.17
3.11
2.25
Texture
1.08
.50
.65
1.25
Table 9. Summary of Apizaco Mano Attribute Means.
Middle
Middle/Late
Late
Late/Terminal
Attribute Formative Formative Formative
Formative
Density
2.33
2.29
2.34
2.32
Porosity
2.46
2.75
2.71
3.67
Texture
1.11
0.00
1.07
.67
Therefore, although metateros often used whatever stone was available locally, it
seems that they had different priorities in choosing stone for their manos and metates.
This observation suggests that toolmakers carefully chose the raw materials for
manufacturing their maize-grinding tools. It also seems to support the idea that
manufacturers chose dense, fine, granular stone for its durability by the Late Formative.
However, to reiterate, there is no gradual trend from the Middle Formative to the
Late/Terminal Formative toward the use of very dense, fine pored, granular stone in
Apizaco.
Mezquital Valley
Unlike the Apizaco sites, the Mezquital Valley sites all come from effectively the
same time period. Therefore, instead of examining the results chronologically, it is more
useful to compare them contextually. Sites listed explicitly in the figures and tables are
64
those that have more than one artifact or where NAA data exists. All remaining sites are
grouped under ‘Other’.
Again, the issue is to determine whether durability was influential in the choice of
raw material for maize-grinding tools and if it can be measured by a combination of the
attributes of stone density, porosity, and texture quality. If durability is related to fine
pores, granular material, and dense stone, then the manos from the Mezquital Valley
would be more durable than the metates (Table 10). There are more manos than metates
made of dense stone, even though the range of dense materials used is greater for manos
(Figure 11 and Figure 12). Almost half of the manos (21 of 43) are made of fine pored
stone as opposed to less than a quarter of the metates (9 of 40) (Figure 13 and Figure 14).
Twenty percent of the manos were granular and only 15% of the metates were granular
(Figure 15 and Figure 16).
Table 10. Summary of Mezquital Valley Mano and Metate Attribute Means.
Manos
Metates
Texture
Texture
Context
Density Porosity Quality Density Porosity Quality
Chapantongo
2.18
3.00
0.67
2.10
3.33
0.17
Ejido
2.35
3.00
0.00
El Choncho
2.07
3.67
0.67
El Ramon
2.37
3.00
0.67
Loma Taxhuada
2.22
3.33
2.00
Los Apaches
2.27
2.00
0.33
Los Perritos
2.33
2.33
1.33
2.31
3.13
0.75
Los Wemas
2.13
3.00
0.50
Other
2.13
2.36
1.09
2.25
2.92
1.00
Paraje Taxhue
2.06
2.00
0.50
1.82
5.00
0.00
Tepetitlan
2.39
2.67
0.67
2.29
3.00
0.33
Zimapantongo
2.12
3.33
0.00
2.24
3.50
1.00
65
Figure 11. Mezquital Valley metate density frequencies g/ml.
66
Figure 12. Mezquital Valley mano density frequencies g/ml.
1
1
Site
Figure 13. Mezquital Valley metate porosity frequencies.
Zimapantongo
2
3
Tepetitlan
33
Paraje Taxhue
2
Other
222
Los Wemas
3
Los Perritos
El Choncho
Ejido
Chapantongo
Number of artifacts
67
6
5
5
4
4
3
3
Fine
Medium
Coarse
2
2
1
11
0
1
2
1
11
Site
Figure 14. Mezquital Valley mano porosity frequencies.
Zimapantongo
2
Tepetitlan
111
Paraje Taxhue
5
Other
2
Los Perritos
3
Los Apaches
Loma Taxhuada
El Ramon
Chapantongo
Number of artifacts
68
7
6
6
5
5
4
4
3
3
Fine
Medium
Coarse
2
2
1
1
1
0
69
7
6
6
4
Granular
Medium
Vesicular
4
3
3
3 3
3
2
2
1
1
11
1
1
1 1
Zimapantongo
1
Tepetitlan
2
1
Paraje Taxhue
Other
Los Wemas
Los Perritos
El Choncho
Ejido
0
Chapantongo
Number of artifacts
5
5
Site
Figure 15. Mezquital Valley metate texture quality frequencies.
70
9
8
8
7
Number of artifacts
6
6
Granular
Medium
Vesicular
5
4
4
3
3
3
2
2
2
2
2
2
2
1
1
1
1
11
1
1
Zimapantongo
Tepetitlan
Paraje Taxhue
Other
Los Perritos
Los Apaches
Loma Taxhuada
El Ramon
Chapantongo
0
Site
Figure 16. Mezquital Valley mano texture quality frequencies.
With that said, for sites that have both manos and metates, the mean density of the
manos is about the same as that of the metates (Table 11, Table 12, and Table 13). A
two-sample t-test, (Table 13), indicates that there is not a significant difference between
the mean densities of manos and metates. Two possible explanations for the similarity of
mean density are as follows: either the density of the Mezquital Valley material does not
vary much or that the various people in the valley preferred similarly dense stone.
71
Table 11. Mezquital Valley Manos Mean Density g/ml.
Context
Chapantongo
Ejido
El Choncho
El Ramon
Loma Taxhuada
Los Apaches
Los Perritos
Los Wemas
Other
Paraje Taxhue
Tepetitlan
Zimapantongo
All sites
Number of
Artifacts
12
0
0
3
3
3
3
0
11
2
3
3
43
Mean
2.18
2.37
2.22
2.27
2.33
2.13
2.06
2.39
2.12
2.21
Standard
Deviation
.1393
.24
.23
.52
.0721
.14
.0071
.1305
.1908
.1987
Table 12. Mezquital Valley Metates Mean Density g/ml.
Context
Chapantongo
Ejido
El Choncho
El Ramon
Loma Taxhuada
Los Apaches
Los Perritos
Los Wemas
Other
Paraje Taxhue
Tepetitlan
Zimapantongo
All sites
Number of
Artifacts
6
3
3
0
0
0
8
2
12
1
3
2
40
Mean
2.10
2.35
2.07
2.31
2.13
2.25
1.82
2.29
2.24
2.22
Standard
Deviation
.2649
.1415
.0443
.2556
.1078
.1856
.0854
.0495
.2099
72
Table 13. Mezquital Valley Mean Density Two Sample T-test, Manos Compared to Metates
Context
Chapantongo
Tepetitlan
Los Perritos
Zimapantongo
All sites
Number of Number of
t Value for
Pr > |t|
Manos
Metates
Equal Variances
12
6
.81
.4312
3
3
1.15
.3152
3
8
.15
.8871
3
2
-.8
.4845
43
40
-.27
.7860
Moreover, the mean porosity scores per site are high for both manos and metates
(Table 14 and Table 15). The mean texture quality scores for both tools vary
considerably (Table 16 and Table 17). However, as in Apizaco, this pattern could be a
result of random chance or could be because many sites have only a small number of
artifacts.
Table 14. Mezquital Valley Manos Mean Porosity Scores. Ordinal Scale of 0 to 5; 0 = No Pores and 5 =
Very Porous.
Context
Chapantongo
Ejido
El Choncho
El Ramon
Loma Taxhuada
Los Apaches
Los Perritos
Los Wemas
Other
Paraje Taxhue
Tepetitlan
Zimapantongo
Number of
Artifacts
12
0
0
3
3
3
3
0
11
2
3
3
Mean
3.00
3.00
3.33
2.00
2.33
2.36
2.00
2.67
3.33
Standard
Deviation
1.04
1.00
1.15
0.00
0.58
0.67
1.41
1.15
0.58
73
Table 15. Mezquital Valley Metates Mean Porosity Scores. Ordinal Scale of 0 to 5; 0 = No Pores and 5 =
Very Porous.
Context
Chapantongo
Ejido
El Choncho
El Ramon
Loma Taxhuada
Los Apaches
Los Perritos
Los Wemas
Other
Paraje Taxhue
Tepetitlan
Zimapantongo
Number of
Artifacts
6
3
3
0
0
0
8
2
12
1
3
2
Mean
3.33
3.00
3.67
3.13
3.00
2.92
5.00
3.00
3.50
Standard
Deviation
1.37
0.00
1.53
1.25
0.00
1.08
0.00
0.71
Table 16. Mezquital Valley Manos Mean Texture Quality Scores. Ordinal scale of 0 to 2; 0 = Vesicular, 1=
Medium, and 2 = Granular.
Context
Chapantongo
Ejido
El Choncho
El Ramon
Loma Taxhuada
Los Apaches
Los Perritos
Los Wemas
Other
Paraje Taxhue
Tepetitlan
Zimapantongo
Number of
Artifacts
12
0
0
3
3
3
3
0
11
2
3
3
Mean
0.67
0.67
2.00
0.33
1.33
1.09
0.50
0.67
0.00
Standard
Deviation
0.78
0.58
0.00
0.58
0.58
0.54
0.71
1.15
0.00
74
Table 17. Mezquital Valley Metates Mean Texture Quality Scores. Ordinal scale of 0 to 2; 0 = Vesicular,
1= Medium, and 2 = Granular.
Context
Chapantongo
Ejido
El Choncho
El Ramon
Loma Taxhuada
Los Apaches
Los Perritos
Los Wemas
Other
Paraje Taxhue
Tepetitlan
Zimapantongo
Number of
Artifacts
6
3
3
0
0
0
8
2
12
1
3
2
Mean
0.17
0.00
0.67
0.75
0.50
1.00
0.00
0.33
1.00
Standard
Deviation
0.41
0.00
1.15
0.71
0.71
0.74
0.58
1.41
Unlike the other sites, people at Zimapantongo did not use any fine pored stone
for their manos (Figure 14). Also, all of Zimpantongo’s manos were vesicular and the
stone was not as dense as the metates (Figure 11, Figure 12, Figure 15, and Figure 16).
However, the low frequency of artifacts may be contributing to this perceived difference.
It would be unusual if Mezquital Valley manos were more durable than metates.
Metates are much more complicated to make and, in general, were designed to last longer
than manos (Cook 1982; Hayden 1987c; Horsfall 1987). The fact that manos were made
from possibly more durable stone indicates that the material was available. Yet, it is
possible that metateros had difficulties finding preferable material in blocks of the
appropriate size for their metates. Alternatively, the metateros may not have had the
skills or expertise necessary to shape the larger, more complicated metate from the
available stone.
75
Factors Determined by Geochemical Analysis
Design or Type of Apizaco Metates
As stated in Chapter One, the Apizaco collection was analyzed to determine if the
footed metates of the Late Formative Period came from the same stone sources as slab
metates of the Middle Formative Period. Group numbers are based on the hierarchical
cluster analysis diagram (see Appendix H). The artifacts in a particular group most likely
came from the same stone formation. The cluster analysis included both manos and
metates. The results for the metates are summarized in Table 18. The shape indicates
whether the body of the metate is a slab (open-faced) or a trough, and whether it is footed
or not. Shape, in this usage, refers to the design of the metate, not the type of the metate.
Table 18. Apizaco Metates Grouped by Source.
Source
Group
Number
1
2
4
14
19
22
25
27
Grinding
Tool
Number
GT 40
GT 2
GT 120
GT 55
GT 109
GT 111
GT 10
GT 95
GT 114
GT 15
GT 37
GT 39
GT 88
GT 22
Site
Amomoloc
Amomoloc
La Laguna
Amomoloc
La Laguna
Amomoloc
Tetel
La Laguna
La Laguna
Tetel
Tetel
Tetel
La Laguna
Tetel
Chronology
Early MF
Early MF
Late MF
Early MF
Late MF
Early MF
MF
Late MF
Late MF
MF
MF
MF
Late MF
MF
Shape
Trough Non-Footed
Trough Non-Footed
Slab Non-Footed
Slab Non-Footed
Trough Non-Footed
Slab Non-Footed
Trough Non-Footed
Slab Non-Footed
Trough Footed
Slab Footed
Slab Footed
Slab Footed
Trough Footed
Non-diagnostic form
It is possible that all of the Apizaco grinding tools come from variants of the same
source. However, results of a geological examination indicated that each of the Apizaco
76
sites might have used a different set of sources to acquire the raw materials for their
metates. Jessica Jones, who was an undergraduate student at California State University,
Sacramento at the time, performed a macroscopic geological examination of the
collection and noted that the basalt grinding tools at each site had a different predominant
mineral content, indicative of different stone sources. For Amomoloc, nine out of twelve
artifacts contained feldspar. Ten out of twelve artifacts from Tetel had mostly olivine
crystals. While La Laguna artifacts were physically and mineralogically mixed, Las
Mesitas artifacts had large quantities of big olivine crystals. Hierarchical clustering data
support the interpretation that each site used independent stone sources (see Appendix
H). Table 18 below lists the metates and their possible source group. Source groups are
based on geochemical similarities.
It seems that during the Middle Formative, slab-bodied metates with feet all came
from the same source and the same site (see Group 22 in Table 18). The artifacts in this
group have a similar appearance (Figure 17). However, based on the grouping of the
non-footed metates, it seems that similar stone sources were used to make both slabbodied and trough-bodied metates (see Group 19 in Table 18). Group 19 contains mostly
Middle Formative non-footed metates. These artifacts appear to be similar to each other
(Figure 18). The observation that the non-footed metates appear in different groups than
the footed metates suggests that non-footed metates came from different sources than
metates with feet. On the other hand, the data in Table 18 also indicate that the Late
Formative metateros likely used some of the same sources as those in the Middle
Formative when making non-footed metates.
77
Figure 17. Middle Formative Period Apizaco slab metates with supports or feet from Tetel.
Figure 18. Apizaco metates from Tetel and La Laguna.
78
The identification of different stone sources for the manufacture of footed versus
non-footed metates supports the interpretation stated in the previous section that, in
Apizaco, Formative Period metate-makers carefully selected their stone materials
primarily when shaping the most complex metate forms of their time. The general
pattern for the Middle Formative reflects an industry dominated by opportunistic stone
selection from convenient nearby formations accompanied by signs of the emergence of
more selective craftsmen. By the Late Formative Period, metate-makers definitely chose
specific stone types for their footed metates. These patterns emerge from the data even
though the sample sizes are small.
Tlachinolpan Stone Sources
The third question was whether metateros of Tlachinolpan were restricted to
using nearby middle Teotihuacan Valley stone sources. Raw materials used at the lower
Teotihuacan Valley sites of Cuanalan, Tezoyuca, and Venta de Carpio, dating to the Late
and Early Terminal Formative Periods, can be accounted for from stone sources nearby in
the lower Teotihuacan Valley (Watson et al. 2006). The authors questioned whether
Tlachinolpan, a contemporary middle Teotihuacan Valley site, also might have been
restricted to nearby stone sources (in the middle valley). Principal component analysis
data are located in Appendix I. Part of the contents of Appendix I are tables with
probable source assignments for each artifact. Sources used are listed in
79
Table 19.
80
Table 19. Stone Source Assignments for Late/Terminal Formative and Classic Period Sites in Teotihuacan
Valley. All Data Except Those for Tlachinolpan Are from Biskowski 1997.
Late/Terminal
Formative/
Classic Sites
Cuanalan (n=12)
01A
02A
1
8.3 %
02B
05A
1
8.3%
05B
08A
11A
13C
14A
1
8.3%
1
20.0%
6
50.0%
1
20.0%
1
8.3%
2
40.0%
0
0
4
5.8%
1
3.3%
2
6.3%
4
5.8%
6
15%
7
10.1%
2
5%
4
5.8%
1
8.3%
Tezoyuca (n=5)
Venta de Carpio (n=6)
Teotihuacan 11: N1E4
and 14:N1E4 (n=32)
Teotihuacan 33:S3W1
(n=16)
1
16.7%
1
2.5%
1
1.5%
3
10%
2
6.3%
2
12.5%
Late/Terminal
Formative/
Classic Sites
23A 28A 28C 61A 62A
Tlachinolpan (n=40)
Pyramid of
Queztalcoatl (n=69)
Maquixco Bajo (n=30)
2
5%
18
26.1%
4
13.3%
13
40.6%
5
31.3%
1
2.5%
3
4.4%
0
1
1.5%
1
6.3%
1
16.7%
4
10%
3
4.4%
1
3.3%
3
9.4%
2
12.5%
62B
1
3.1%
1
6.3%
65A
Gen.
UnAnd. assigned
Cuanalan (n=12)
Tezoyuca (n=5)
Venta de Carpio (n=6)
Tlachinolpan (n=40)
Pyramid of
Queztalcoatl (n=69)
Maquixco Bajo (n=30)
Teotihuacan 11: N1E4
and 14:N1E4 (n=32)
Teotihuacan 33:S3W1
(n=16)
0
2
5%
1
1.5%
1
3.3%
0
2
2.9%
0
1
2.5%
1
1.5%
3
9.4%
2
33.3%
3
7.5%
3
4.4%
1
3.3%
3
9.4%
1
6.3%
0
0
18
60.0%
1
3.1%
1
8.3%
1
20.0%
2
33.3%
17
42.5%
17
24.6%
1
3.3%
4
12.5%
4
25%
It is clear that Tlachinolpan was not restricted to using only nearby middle valley
stone sources (
81
Table 19). Artifacts with source assignments come from not just the middle valley (e.g.,
source 2A), but also the lower valley (such as, source 14A) and from sources outside the
Teotihuacan Valley (source 62A and 62B). Tlachinolpan apparently used many of the
same sources as those used by contemporary lower valley sites (Cuanalan, Tezoyuca, and
Venta de Carpio) as well as some of the same sources used by Classic Period
Teotihuacan.
Forty-two point five percent of the artifacts did not have identifiable stone
sources. Compared to the other sites in
82
Table 19, this percentage is high. It is possible that the samples were contaminated, but
this is unlikely. It is more likely that these materials came from outside the Teotihuacan
Valley. A higher frequency of imported materials could be related to the relatively high
status of the inhabitants of Tlachinolpan and to the high frequency of well-crafted footed
metates found there.
Summary
The results discussed in this chapter demonstrate that there are many factors that
influence the choice of raw materials for grinding tools and that the factors cannot
necessarily be separated from each other. For example, although durability may be
important, one could not isolate durability as a factor without also taking in consideration
stone texture or raw material availability. The problem is that stone density, porosity,
and texture quality may not combine in a linear manner that reflects a consistent
preference for durability. Some stone types with few pores weigh than more porous
stone (e.g., compare GT# 72 and GT# 133 to GT# 101 in Appendix C; and GT# 97 and
GT# 90 to GT# 1 and GT# 108 in Appendix D). In addition, some porphyritic stone is
hard while others are not.
A second point is that the importance of some factors changed over time and
location. For instance, some sites in the Mezquital Valley demonstrated that residents
preferred manos made from dense stone whereas other contemporaneous sites showed a
preference for metates made from dense stone. However, without further source
analyses, one cannot rule out the possibility that some Mezquital Valley residents
83
preferred nearby raw material sources. Apizaco mano and metate stone preferences vary
from the Middle Formative Period to the Late/Terminal Formative Period.
A third problem is stone availability. While preferable raw materials may have
been available to make manos, sufficiently large boulders of the preferred material may
not have been available to make metates. This last factor would be very difficult to
examine since quarries available in the past may not exist in the present and even if they
did, it is hard to measure the absence of material. Because quarries from the past may be
used up or may no longer exist for other reasons, it is difficult to assess where particular
artifacts were made.
In summary, the durability of grinding tools in Apizaco and the Mezquital Valley
may not be measureable by combining stone density, porosity, and stone texture.
Apizaco metateros preferred certain stone sources for making footed metates. The raw
material for Tlachinolpan maize-grinding tools came from stone quarries both inside and
outside of the Teotihuacan Valley. Some of the factors that influenced choice of raw
materials for Ancient Mexican maize-grinding tools may or may not have included
durability, appears to have included metate design, did not include restrictions to
available stone sources.
84
Chapter 5
DISCUSSION AND CONCLUSIONS
As stated in Chapter 1, this thesis identified factors that influenced the choice of raw
materials for the manufacture and usage of maize-grinding tools from Ancient Mexico.
The study intended to answer three questions:
(1) Did durability influence the choice of stone for the production of manos
and metates in the Apizaco region or in the Mezquital Valley?
(2) Was the design or type of metate important for Apizaco metateros when
selecting raw material?
(3) Was Tlachinolpan restricted to using nearby Middle Teotihuacan Valley
stone sources for the production of maize-grinding tools?
This chapter will discuss the answers to the above questions.
Durability
One goal of this thesis was to discover whether one could measure durability by a
combination of three artifact attributes: stone density, porosity, and texture quality. If
durability can be measured by the three artifact attributes listed above, then one would
expect to see high density, low porosity, and granular stone texture co-occurring on many
artifacts. This was not the case. Because many grinding tools were not made from
dense, fine pored, granular stone, at least two possibilities are apparent. One, these three
attributes are not a good measure for durability; for example, maybe only two of the three
attributes measure durability. Two, the measures of durability as proposed in this thesis
are flawed. Therefore, it is still unclear if durability was influential in decisions
85
regarding source material for maize-grinding tools in the Apizaco region or the Mezquital
Valley.
Apizaco
In fact, the data do not show a gradual trend either toward or away from high
density, low porosity, and granular stone texture. Metates show a decrease in stone
density in the Middle Formative followed by an increase in stone density in the Late
Formative. They also exhibit an increase in coarseness and vesicularity until the Late
Formative. As stated in Chapter 4, mano density and texture quality remains consistent
over time whereas stone coarseness for manos increases over time. Maybe density and
coarseness alone represent durability. Moh’s hardness scale data would verify whether
any artifact attributes provide durability measures.
It is apparent that at some sites, people would manufacture metates from high
density, fine pored, and granular textured stone and people at other sites would
manufacture their manos instead of their metates from similar material. It is possible that
metateros from different sites preferred different stone but this could also be indicative of
resource availability.
Mezquital Valley
The metates from the Mezquital Valley show a wider variation of stone texture,
porosity, and stone density. Manos showed less variety than the metates. Since the
artifacts showed more variation in raw material, it seems that expediency, not durability,
was the important factor. Expediency is indicated by the differences in raw material used
by each site. With that said, there is still a tendency for metates toward coarse, dense
86
stone with medium pores. It would seem that grinding maize was still important but not
as important as in the Late Formative. Other items were supplementing maize in the diet.
Another reason for the variety of materials used could be the mobility of the
people. Michael Spence (Spence et al. 2011) mentioned that, based on isotopic analysis
of teeth and bones, certain groups of people in Chapantongo were more mobile during
their lifetime. Some of the residents were born in Chapantongo, went to live in the
highlands later in their lives, and came back to Chapantongo where they were buried.
Those who were mobile may not have wished to invest time and energy into the
production of complex stone tools.
Design or Metate Type
Chapter 4 states that Middle Formative, slab-shaped metates with feet all came
from the same source and the same source. Non-footed metates came from different
sources than metates with feet. Late Formative metateros likely used some of the same
sources as those in the Middle Formative when making non-footed metates. However, it
should be acknowledged that these conclusions are not exact. “While geochemistry and
petrography can also furnish an independent data set to confirm or rule out quarry
sources, it is targeted and intensive field study that remains the most important means of
identifying and studying the site type on which we focus our interest. As far as we are
able to determine, no quarry has been found merely on the basis of geochemistry,
whatever the analytical techniques used” (Schneider and LaPorta 2008:34, emphasis in
original). Surveys to identify Apizaco maize-grinding tool quarries should be performed
in the future to provide further evidence to support or alter the above conclusions.
87
Tlachinolpan Stone Sources
Watson et al. (2006) postulated that the lower Teotihuacan Valley sites of
Cuanalan, Tezoyuca, and Venta de Carpio, dated to the Late and Early Terminal
Formative Periods, were restricted to using lower Teotihuacan Valley stone sources for
their grinding tools. Was contemporary Tlachinolpan restricted to using middle valley
quarries? Chapter 4 results indicate that Tlachinolpan, a middle Teotihuacan Valley site,
was not restricted to using only middle valley sources. It is possible that the appearance
of a lower valley restriction is based on the low number of artifacts available for study
(n=23) whereas the middle valley site study had access to more artifacts (n=40). Not
surprisingly, Tlachinolpan grinding tools came from some, but not all, of the same
sources as used by the Pyramid of Quetzalcoatl, a contemporary middle valley collection.
Both collections contained the same number of tools from unidentified sources (n=17),
although for Tlachinolpan the percentage was much higher. What is surprising is that so
few of the artifacts (n=4) came from Cerro Malinalco and Cerro Gordo given the
proximity of these sources to the site. It is possible that, although these sources were
close, metate-makers may have had access to more preferable raw materials elsewhere.
Another interesting observation was the relatively high number of artifacts from the
source preferred by Cuanalan people (13C), about 15%. These numbers suggest a pattern
of reciprocal exchange or maybe some familial connection. Yet, one cannot rule out the
fact that source 13C is a Patlachique Range source that exists in the middle valley. These
exchange connections were less important by the Classic Period as indicated by the
increased use of both Cerro Malinalco and Cerro Gordo sources. Several sources were
88
not used by any of the sites in this study. Based on the pattern of usage of nearby
sources, distance was not a factor. One further observation is that five of the
Tlachinolpan artifacts from unidentified sources may come from the same sources as
some of the Apizaco artifacts. In a previous paper (Watson et al. 2006), principal
component analysis showed an overlap of possible stone sources between some artifacts
from the Apizaco region and some from the Teotihuacan Valley. Similar studies of the
Apizaco region could provide more evidence of overlapping source usage, which might
indicate a closer connection to the two regions.
Summary
How best to tie all these factors together into a coherent whole? The importance
of durability, identification of choice in raw material, and identification of stone source
usage are more pieces to the puzzle of how maize preparation and grinding stone
technology changed in Ancient Mexico over time.
Maize preparation methods and technology both become more important leading
up to the Classic Period. Then another technological change occurs in the Epiclassic.
Exchange and raw material acquisition patterns change as maize preparation changes
from the Formative through the Classic Periods. Sources not used in one period become
important in a later period as political boundaries change or resource availability changes.
Rock sources also change in importance as manufacturing skill levels change. Although
the factors are identified and investigated separately, it is clear that they are all part of a
whole thought process.
89
APPENDICES
90
APPENDIX A
Mezquital Valley Mano Density, Porosity, Texture Quality Data, Frequencies, and
Percentages.
Site = Chapantongo
Bag
Number
3
23
34
41
76
76
82
83
86
90
91
Item
Number
1
1
1
1
1
3
1
3
1
1
1
Mass
.32
.36
.82
1.47
.92
.65
.30
.24
.53
.35
.32
Volume
.16
.17
.38
.67
.45
.32
.14
.11
.24
.14
.15
Density
2.05
2.18
2.15
2.22
2.06
2.07
2.11
2.17
2.19
2.58
2.22
Porosity
Medium
Medium
Coarse
Coarse
Medium
Fine
Fine
Fine
Coarse
Fine
Coarse
Porosity
Score
3
3
4
5
3
2
2
2
4
2
4
Texture
Quality
Medium
Vesicular
Vesicular
Vesicular
Vesicular
Granular
Granular
Medium
Vesicular
Medium
Vesicular
Texture
Score
1
0
0
0
0
2
2
1
0
1
0
Mass
.44
.33
.55
Volume
.18
.14
.24
Density
2.53
2.38
2.27
Porosity
Fine
Fine
Coarse
Porosity
Score
2
2
4
Texture
Quality
Vesicular
Vesicular
Granular
Texture
Score
0
0
2
Porosity
Coarse
Medium
Fine
Porosity
Score
4
3
2
Texture
Quality
Vesicular
Medium
Medium
Texture
Score
0
1
1
Site = Tepetitlan
Bag
Number
53
54
56
Item
Number
2
2
1
Site = El Ramon
Bag
Number
28
32
35
Item
Number
1
1
1
Mass
.33
1.83
.85
Volume
.15
.81
.32
Density
2.20
2.27
2.65
91
Site = Los Apaches
Bag
Number
62
62
62
Item
Porosity Texture
Texture
Number Mass Volume Density Porosity Score
Quality
Score
2
.47
.18
2.58
Fine
2
Medium
1
3
.32
.13
2.57
Fine
2
Vesicular
0
5
.07
.04
1.67
Fine
2
Vesicular
0
Site = Los Perritos
Bag
Number
42
81
81
Item
Porosity Texture Texture
Number Mass Volume Density Porosity
Score
Quality
Score
5
.75
.31
2.41
Medium
3
Medium
1
1
.71
.31
2.27
Fine
2
Medium
1
2
.50
.22
2.31
Fine
2
Granular
2
Site = Paraje Taxhue
Bag
Number
11
11
Item
Porosity Texture
Texture
Number Mass Volume Density Porosity
Score
Quality
Score
3
.42
.21
2.06
Medium
3
Vesicular
0
4
.12
.06
2.07
Fine
1
Medium
1
Site = Zimapantongo
Bag
Number
6
610
610
Item
Porosity Texture
Texture
Number Mass Volume Density Porosity
Score
Quality
Score
1
.73
.39
1.90
Coarse
4
Vesicular
0
3
.63
.28
2.24
Medium
3
Vesicular
0
5
.28
.13
2.22
Medium
3
Vesicular
0
92
Site = Other
Bag
Number
4
5
13
18
24
31
46
47
58
60
64
67
68
72
Item
Porosity Texture
Texture
Number Mass Volume Density Porosity
Score
Quality
Score
1
.24
.12
2.09
Fine
2
Medium
1
2
.13
.06
2.10
Fine
1
Medium
1
1
1.41
.60
2.37
Coarse
4
Granular
2
1
.59
.30
1.96
Coarse
4
Granular
2
3
.31
.13
2.33
Fine
2
Medium
1
1
.28
.14
2.05
Fine
2
Medium
1
1
.63
.33
1.93
Medium
3
Medium
1
1
.45
.20
2.24
Fine
2
Medium
1
1
.63
.31
2.03
Medium
3
Medium
1
1
.30
.13
2.27
Medium
3
Vesicular
0
1
.40
.21
1.96
Fine
2
Medium
1
1
.59
.25
2.34
Fine
2
Granular
2
2
.22
.10
2.20
Medium
3
Granular
2
2
1.18
.53
2.25
Medium
3
Granular
2
Number of artifacts per site.
Number of
Cumulative Cumulative
Site
Artifacts Percent Frequency
Percent
Chapantongo
11
26.19
11
26.19
Tepetitlan
3
7.14
14
33.33
El Ramon
3
7.14
17
40.48
Los Apaches
3
7.14
20
47.62
Los Perritos
3
7.14
23
54.76
Other
14
33.33
37
88.10
Paraje Taxhue
2
4.76
39
92.86
Zimapantongo
3
7.14
42
100.00
93
APPENDIX B
Mezquital Valley Metate Density, Porosity, Texture Quality Data, Frequencies, and
Percentages.
Site = Chapantongo
Bag
Number
78
83
88
92
Item
Number
1
1
1
1
Mass
2.07
.74
.41
.36
Volume
.95
.43
.16
.17
Density
2.18
1.71
2.56
2.11
Porosity
Fine
Medium
Fine
Medium
Porosity
Score
2
3
2
3
Texture
Quality
Vesicular
Vesicular
Medium
Vesicular
Texture
Score
0
0
1
0
Site = Tepetitlan
Bag
Number
52
55
80
Item
Porosity Texture
Number Mass Volume Density Porosity
Score
Quality
1
Medium
3
Medium
1
1.16
.51
2.28
Medium
3
Vesicular
1
.56
.26
2.21
Medium
3
Vesicular
Texture
Score
1
0
0
Site = Los Perritos
Bag
Number
42
42
43
43
43
48
49
81
Item
Porosity Texture
Texture
Number Mass Volume Density Porosity
Score
Quality
Score
2
3.31
1.23
2.70
Fine
1
Granular
2
4
1.76
.77
2.28
Coarse
5
Vesicular
0
1
2.11
.93
2.28
Coarse
4
Vesicular
0
2
1.46
.64
2.30
Coarse
4
Medium
1
3
1.42
.81
1.76
Medium
3
Medium
1
1
.82
.36
2.31
Medium
3
Medium
1
1
1.83
.73
2.53
Fine
2
Medium
1
3
.30
.14
2.25
Medium
3
Vesicular
0
Site = Paraje Taxhue
Bag
Item
Porosity Texture
Texture
Number Number Mass Volume Density Porosity Score
Quality
Score
11
1
1.80
.95
1.89
Coarse
5
Vesicular
0
94
Site = Zimapantongo
Bag
Item
Porosity Texture
Texture
Number Number Mass Volume Density Porosity Score
Quality
Score
610
2
2.53
1.15
2.20
Coarse
4
Vesicular
0
Site = Other
Bag
Item
Porosity Texture
Texture
Number Number Mass Volume Density Porosity
Score
Quality
Score
1
1
.71
.31
2.31
Medium
3
Medium
1
5
1
1.03
.50
2.06
Medium
3
Medium
1
8
1
.60
.26
2.32
Medium
3
Vesicular
0
22
1
4.19
Medium
3
Vesicular
0
33
1
.95
.44
2.16
Fine
2
Medium
1
39
1
2.20
.98
2.25
Coarse
4
Medium
1
45
1
.77
.33
2.33
Medium
3
Medium
1
50
1
.28
.12
2.33
Fine
2
Medium
1
58
2
.32
.15
2.12
Coarse
4
Vesicular
0
65
1
1.98
.98
2.03
Coarse
5
Vesicular
0
71
1
Coarse
4
Vesicular
0
333
2
1.02
.41
2.49
Medium
3
Vesicular
0
333
3
.92
.42
2.21
Medium
3
Vesicular
0
Number of artifacts per site.
Site
Chapantongo
Tepetitlan
Los Perritos
Other
Paraje Taxhue
Zimapantongo
Number of
Cumulative Cumulative
Artifacts Percent Frequency
Percent
4
13.33
4
13.33
3
10
7
23.33
8
26.67
15
50.00
13
43.33
28
93.33
1
3.33
29
96.67
1
3.33
30
100.00
95
APPENDIX C
Apizaco Mano Density, Porosity, Texture Quality Data, Frequencies, and Percentages.
Site = Amomoloc
Grinding
Porosity Texture
Texture
Tool ID Mass Volume Density Porosity Score Quality
Score
GT 3
.32
.14
2.26
Coarse
4
Vesicular
0
GT 4
.36
.15
2.45
Fine
2
Medium
1
GT 52
.53
.22
2.40
Medium
3
Vesicular
0
GT 53
.35
.15
2.41
Fine
2
Medium
1
GT 56
1.52
.69
2.21
Coarse
5
Vesicular
0
GT 68
.26
.12
2.12
Medium
3
Medium
1
GT 72
.28
.13
2.18
Fine
2
Granular
2
GT 78
.67
.33
2.04
Coarse
4
Vesicular
0
GT 80
.27
.14
1.97
Fine
2
Medium
1
GT 81
.57
.22
2.58
Fine
1
Granular
2
GT 101
.58
.25
2.30
Coarse
4
Vesicular
0
GT 103
.57
.23
2.49
Fine
1
Medium
1
GT 104
.82
.41
2.01
Coarse
4
Medium
1
GT 127
.84
.33
2.54
Medium
3
Medium
1
GT 129
.69
.28
2.46
Medium
3
Granular
2
GT 132
.35
.16
2.20
Medium
3
Medium
1
GT 133
.78
.38
2.05
Fine
1
Granular
2
GT 134
.53
.24
2.21
Medium
3
Medium
1
GT 139
1.22
.49
2.49
Fine
1
Granular
2
GT 142
.77
.36
2.13
Coarse
4
Medium
1
GT 144
.68
.30
2.25
Fine
2
Medium
1
GT 145
.49
.19
2.62
Fine
0
Granular
2
GT 148
.26
.11
2.33
Fine
2
Medium
1
GT 149
.47
.20
2.41
Fine
0
Granular
2
GT 150
.75
.31
2.42
Medium
3
Medium
1
GT 151
.78
.31
2.55
Fine
2
Medium
1
GT 154
.54
.21
2.59
Fine
0
Granular
2
GT 157
.29
.11
2.57
Coarse
5
Medium
1
96
Site = La Laguna
Grinding
Porosity Texture
Texture
Tool ID Mass Volume Density Porosity Score Quality
Score
GT 73
.48
.20
2.40
Fine
1
Medium
1
GT 74
.82
.33
2.48
Fine
1
Granular
2
GT 82
.48
.21
2.36
Coarse
4
Vesicular
0
GT 93
.61
.27
2.29
Fine
1
Medium
1
GT 94
.70
.30
2.35
Fine
1
Granular
2
GT 102
.57
.23
2.48
Coarse
4
Medium
1
GT 106
.83
.35
2.42
Fine
2
Medium
1
GT 113
2.78
1.25
2.23
Medium
3
Medium
1
GT 117
.52
.26
1.99
Fine
2
Medium
1
GT 118
.78
.37
2.11
Coarse
5
Medium
1
GT 119
.25
.10
2.52
Fine
2
Granular
2
GT 122
.33
.17
1.98
Medium
3
Medium
1
GT 126
.50
.22
2.24
Coarse
5
Medium
1
GT 131
.37
.16
2.37
Coarse
4
Medium
1
GT 135
.50
.21
2.36
Medium
3
Medium
1
GT 136
.93
.42
2.23
Fine
2
Medium
1
GT 140
1.49
.58
2.57
Fine
1
Granular
2
GT 141
.74
.29
2.58
Coarse
4
Medium
1
GT 143
.42
.20
2.10
Coarse
5
Vesicular
0
GT 147
.43
.19
2.28
Coarse
5
Medium
1
GT 155
.55
.22
2.55
Fine
1
Granular
2
GT 165
1.33
.54
2.48
Fine
2
Medium
1
GT 177
.29
.12
2.52
Fine
2
Medium
1
GT 181
.84
.36
2.33
Medium
3
Vesicular
0
GT 182
.57
.25
2.28
Medium
3
Vesicular
0
GT 184
1.12
.46
2.44
Fine
2
Granular
2
GT 187
.25
.11
2.27
Fine
2
Medium
1
GT 188
.29
.13
2.21
Medium
3
Medium
1
Site = Las Mesitas
Grinding
Porosity Texture
Texture
Tool ID Mass Volume Density Porosity Score Quality
Score
GT 152
.91
.39
2.34
Coarse
5
Medium
1
GT 153
.51
.22
2.31
Medium
3
Medium
1
GT 170
.99
.43
2.31
Medium
3
Vesicular
0
97
Site = Tetel
Grinding
Porosity Texture
Texture
Tool ID Mass Volume Density Porosity Score Quality
Score
GT 11
.52
.22
2.35
Medium
3
Vesicular
0
GT 16
.64
.27
2.41
Medium
3
Vesicular
0
GT 21
.52
.25
2.11
Fine
2
Vesicular
0
GT 28
.98
.42
2.32
Medium
3
Vesicular
0
GT 38
.54
.23
2.36
Fine
2
Vesicular
0
GT 41
.51
.22
2.39
Fine
2
Vesicular
0
GT 47
.54
.23
2.35
Coarse
4
Vesicular
0
GT 48
.37
.18
2.02
Medium
3
Vesicular
0
Site = Other
Grinding
Porosity Texture
Texture
Tool ID Mass Volume Density Porosity Score Quality
Score
GT 19
.36
.15
2.36
Medium
3
Vesicular
0
GT 29
.87
.38
2.28
Medium
3
Vesicular
0
GT 30
.39
.15
2.57
Medium
3
Vesicular
0
GT 35
.99
.45
2.21
Medium
3
Vesicular
0
GT 49
.37
.15
2.44
Fine
2
Medium
1
GT 51
.54
.24
2.24
Medium
3
Medium
1
Number of artifacts per site.
Site
Amomoloc
La Laguna
Las Mesitas
Other
Tetel
Number of
Cumulative Cumulative
Artifacts Percent Frequency
Percent
28
38.36
28
38.36
28
38.36
56
76.71
3
4.11
59
80.82
6
8.22
65
89.04
8
10.96
73
100
98
APPENDIX D
Apizaco Metate Density, Porosity, Texture Quality Data, Frequencies, and Percentages.
Site = Amomoloc
Grinding
Porosity Texture
Texture
Tool ID Mass Volume Density Porosity Score Qualtiy
Score
GT 1
.79
.33
2.43
Medium
3
Vesicular
0
GT 2
.87
.40
2.17
Coarse
4
Vesicular
0
GT 40
4.25
1.77
2.39
Fine
2
Granular
2
GT 44
.48
.20
2.36
Medium
3
Medium
1
GT 55
.85
.33
2.57
Fine
2
Granular
2
GT 64
.62
.25
2.44
Fine
2
Medium
1
GT 89
.37
.16
2.31
Medium
3
Medium
1
GT 95
1.50
.65
2.32
Medium
3
Medium
1
GT 97
.96
.46
2.09
Fine
1
Medium
1
GT 105
.50
.21
2.42
Medium
3
Medium
1
GT 110
.27
.15
1.86
Medium
3
Medium
1
GT 111
2.66
1.12
2.37
Fine
2
Medium
1
GT 112
3.13
1.30
2.41
Fine
2
Granular
2
99
Site = La Laguna
Grinding
Porosity Texture
Texture
Tool ID Mass Volume Density Porosity Score Quality
Score
GT 57
0.96
0.39
2.49
Medium
3
Medium
1
GT 58
1.30
0.69
1.89
Medium
3
Vesicular
0
GT 63
0.46
0.23
2.03
Fine
2
Vesicular
0
GT 66
1.56
0.69
2.26
Coarse
4
Medium
1
GT 77
0.65
0.30
2.17
Medium
3
Vesicular
0
GT 84
0.42
0.17
2.55
Medium
3
Medium
1
GT 87
0.30
0.13
2.24
Medium
3
Vesicular
0
GT 88
1.16
0.50
2.35
Medium
3
Medium
1
GT 90
0.58
0.27
2.17
Fine
2
Medium
1
GT 96
8.37
3.62
2.31
Medium
3
Medium
1
GT 98
0.36
0.16
2.22
Medium
3
Medium
1
GT 99
0.57
0.24
2.37
Coarse
4
Medium
1
GT 100
0.64
0.28
2.34
Coarse
4
Medium
1
GT 107
0.48
0.24
1.99
Coarse
4
Vesicular
0
GT 108
0.77
0.32
2.41
Coarse
5
Medium
1
GT 109
1.43
0.74
1.93
Fine
2
Vesicular
0
GT 114
1.97
0.90
2.19
Coarse
4
Vesicular
0
GT 116
3.25
1.40
2.33
Fine
2
Medium
1
GT 120
1.56
0.73
2.16
Medium
3
Medium
1
GT 124
0.41
0.17
2.48
Coarse
4
Medium
1
GT 125
0.43
0.18
2.39
Medium
3
Medium
1
GT 130
0.37
0.17
2.22
Medium
3
Granular
2
GT 137
0.30
0.13
2.43
Fine
2
Medium
1
GT 138
0.71
0.30
2.36
Medium
3
Medium
1
GT 146
0.40
0.18
2.31
Coarse
4
Medium
1
GT 162
2.57
1.13
2.29
Fine
2
Medium
1
GT 163
1.08
0.50
2.15
Medium
3
Medium
1
GT 167
0.28
0.16
1.75
Medium
3
Vesicular
0
GT 169
2.51
1.13
2.22
Coarse
4
Vesicular
0
GT 171
0.45
0.23
1.97
Medium
3
Medium
1
GT 173
1.63
0.76
2.14
Coarse
4
Vesicular
0
GT 174
1.48
0.65
2.28
Fine
2
Medium
1
GT 175
2.38
1.25
1.91
Medium
3
Vesicular
0
GT 176
1.21
0.54
2.24
Medium
3
Vesicular
0
GT 178
0.65
0.30
2.16
Medium
3
Vesicular
0
GT 183
1.38
0.58
2.38
Medium
3
Vesicular
0
GT 185
0.39
0.16
2.42
Medium
3
Medium
1
100
Site = Las Mesitas
Grinding
Porosity Texture Texture
Tool ID Mass Volume Density Porosity Score Quality
Score
GT 67
.23
.10
2.30
Fine
2
Medium
1
GT 75
.86
.36
2.41
Fine
2
Granular
2
GT 76
.94
.39
2.40
Fine
2
Medium
1
GT 115
1.57
.68
2.33
Medium
3
Medium
1
Site = Tetel
Grinding
Porosity Texture
Texture
Tool ID Mass Volume Density Porosity Score Quality
Score
GT 10
.85
.37
2.34
Coarse
4
Vesicular
0
GT 15
.68
.32
2.13
Medium
3
Vesicular
0
GT 18
1.39
.69
2.01
Medium
3
Medium
1
GT 20
.50
.21
2.34
Medium
3
Vesicular
0
GT 37
1.66
.75
2.22
Medium
3
Medium
1
GT 39
.72
.32
2.28
Medium
3
Medium
1
Number of artifacts per site.
Number of
Cumulative Cumulative
Site
Artifacts Percent Frequency
Percent
Amomoloc
13
21.67
13
21.67
La Laguna
37
61.67
50
83.33
Las Mesitas
4
6.67
54
90
Tetel
6
10
60
100
101
APPENDIX E
BASIC GRINDING TOOL FORM
APIZACO GRINDING TOOL BASIC FORM (7/12/2002)
1. DATE
2. SITE
3. COLLECTION
4. GRINDING TOOL NUMBER
5. Item Definition : -1 0 = mano 1 = metate 2 = pestle 3 = mortar
9
6. Hands: -1 0 = 1-handed only 1 = 1-2 hands 2 = 2 hands
9
7. Motion: -1 0 = tight rotary 1 = loose rotary 2 = reciprocal 9
8. Material: -1 0 = basalt 1 = andesite 2 = rhyolite 3 = granite 9
9. Color: -1 0 = black 1 = gray 2 = brown 9
10. Porosity: -1 0 = none 1 = v. fine 2 = fine 3 = medium 4 = porous 5 = v. porous
11. Texture Quality: -1 0 = vesicular 1 = vesicular/granular 2 = granular
9
12. Crystal Size: -1 0 = < 1mm 1 = 1-2mm
2 = 2-5 mm 3 = >5mm
9
13. Length:
mm
15. Max. Thickness
17. Mass
14. Width
mm
Kg
mm
16. Min. Thickness
18. Volume
9
mm
Liters
102
APPENDIX F
SAMPLE MANO FORM
APIZACO MANO FORM (7/12/2002)
1. DATE
2. SITE
3. COLL.
5. Part : -1 0 = isolated surface 1 = midsection 2 = end
4. GT #
3 = both ends
9
STROKE CHARACTERISTICS:
6. PROB. HAND POSITION:: -1 0 = single focus 1 = shoulder spaced 2 = at ends (beyond shoulder)
9
7. GRIP: -1 0 = above 1 = forward 2 = overhang/end 9
8. OVERHANG REDUCTION: -1 0 = no 1 = yes
9
9. TROUGH REDUCTION: -1 0 = no 1 = yes 9
10. USE SYMMETRY: -1 0 = none 1 = bilateral 2 = quadrilateral 3 = quad+ 4 = bilat+ 5 = tri/trap 9
11. MAJOR USED FACES: -1 0 1
2
3
4
5
9
12. ROTATION/EROSION: -1 0 = none
1 = single direction of F1
2 = dual direction of F1
3 = single F1 and F3
4 = dual F1, single F3 5 = dual F1 and F3
9
13. ROTATION SYMMETRY: -1 0 = none 1 = dual F1 only 2 = F1 rolled to F3 3 = F1 flipped to
F3
4 = F1 rolled and flipped to F3 5 = F1 only rolled/flipped to F2/F4 6 = F1/F3 rolled/flipped to
F2/F4
9
GENERAL SHAPE/WEAR CHARACTERISTICS:
14. TRVPF1: -1 0 = circ 1 = thk oval 2 = thin oval 3 = square 4 = rectangular 5 = parallelogram 6 =
triangular 7 = trapezoid 8 = D-shaped 10 = lenticular 11 = oval with face applied 12 = square w/rnd
crnrs 13 = parallelogram w/rnd crnrs 14 = assymetric lenticular 15 = oval trapezoid
9=
15. OHPF1: -1 0 = circ 1 = thk oval 1 = thin oval 2 = square 3 = rectangular 5 = lenticular
9
16. C1POL: -1
17. C2POL: -1
18. C3POL: -1
19. C4POL: -1
0 = none
0 = none
0 = none
0 = none
20. C1PRF: -1
21. C2PRF: -1
22. C3PRF: -1
23. C4PRF: -1
0 = flat
0 = flat
0 = flat
0 = flat
24. C1CRN: -1
25. C2CRN: -1
26. C3CRN: -1
27. C4CRN: -1
1
1
1
1
2
2
2
2
1 = sl. cvx
1 = sl. cvx
1 = sl. cvx
1 = sl. cvx
0 = v. round
0 = v. round
0 = v. round
0 = v. round
3
3
3
3
4 = very polished
4 = very polished
4 = very polished
4 = very polished
2 = cvx
2 = cvx
2 = cvx
2 = cvx
1 = sl. defined
1 = sl. defined
1 = sl. defined
1 = sl. defined
5 = worn/damaged
5 = worn/damaged
5 = worn/damaged
5 = worn/damaged
9
9
9
9
9
9
9
9
2 = defined
2 = defined
2 = defined
2 = defined
3 = very defined
3 = very defined
3 = very defined
3 = very defined
9
9
9
9
28. C1CTR: -1 0 = bulges toward end 1 = no narrowing 2
3
4 = much narrowing 5 =
narrowing/cvx 9
29. C1END: -1 0 = sl. cvx., crnrs def 1 = sl. cvx, crnrs rnd 2 = approx semicirc. 3 = sl. pointed 4 = v.
pointed 5 = sl. cvx, sl. divergent 6 = flat, crnrs def
9
30. C2CTR: -1 0 = bulges toward end 1 = no narrowing 2
3
4 = much narrowing 5 =
narrowing/cvx 9
31. C2END: -1 0 = sl. cvx., crnrs def 1 = sl. cvx, crnrs rnd 2 = approx semicirc. 3 = sl. pointed 4 = v.
pointed
5 = sl. cvx, sl. divergent 6 = flat, crnrs def
9
103
32. END POLISH: -1 0 = no 1 = p/sl. tejolote use 2 = used as tejolote 3 = reworked as tejolote 4 =
trough 9
33. OHANG SHAPE: -1 0 = none 1 = cut mainly on one face 2 = globular 3 = conical 4 =
glob/conical 5 = damage/reworked
9
34. FINISHED: -1 0 = no 1 = poss. yes 2 = yes
9
35. REUSED: -1 0 = no 1 = building stone 2 = hammer
3 = anvil
9
OVERHANG DIMENSIONS:
36. OLENGTH:
mm
37. OWIDTH:
39. AVG CONTACT SURF. per mm of (functioning) LENGTH:
mm
38. OTHICK:
mm2
mm
104
APPENDIX G
SAMPLE METATE FORM
APIZACO METATE FORM (7/12/2002)
1. DATE
2. SITE
3. COLL.
4. GT #
5. Part : -1 0 = interior 1 = undet. brdr 2 = side 3 = end 4 = corner
5 = side + 2 crnrs 6 = end + 2 crnrs 7 = 3+ crnrs 8 = isol. support
9
6. Side: -1 0 = unknown 1 = left 2 = right 3 = both
9
7. End: -1 0 = unknown 1 = proximal 2 = distal 9
8. Other Orientation: -1 0 = NW/SE 1 = NE/SW
9
9. Restriction: -1 0 = restricted 1 = open 2 = open/overhang 3 = overhang
9
General Morphology:
10. LNG CCV: -1 0 = flat 1 = sl.ccv 2 = ccv 3 = v.ccv 9
11. LAT CCV: -1 0 = flat 1 = sl.ccv 2 = ccv 3 = v.ccv 9
12. LAT CUT: -1 0 = v. cvx nr shldr 1 = sl cvx 2 = flat 3 = unif. curve 4 = ccv nr shldr 5 = vert wall 9
13. LNG CUT: -1 0 = v. cvx nr shldr 1 = sl cvx 2 = flat 3 = unif. curve 4 = ccv nr shldr 5 = vert wall 9
14. SIDE WALLS: -1 0 = none 1 = vert/trough 1 = shallow bowl 2 = deep bowl
9
15. END WALLS: -1 0 = none 1 = vert/trough 1 = shallow bowl 2 = deep bowl
9
16. SIDE/INDET. SHOULDER: -1 0 = small, incompletely reduced 1 = elevated, unused
3 = elevated, used 4 = continuous from interior 5 = overhang track
9
17. END SHLDRS: -1 0 = small, incompletely reduced 1 = elevated, unused
3 = elevated, used 4 = lipped 5 = continuous from interior
9
18. MAJOR CORNERS: -1 0 = unclear 1 = round 2 = sl. defined 3 = defined
9
19. PLAN VIEW SHAPE: -1 0 = circular 1 = oval 2 = rect. borders cvx
3 = rect., ends only cvx 4 = rect., brdrs straight 5 = borders cvx 6 = brdrs straight
9
20. FINISHED: -1 0 = no 1 = poss. yes 2 = yes
9
21. REUSED: -1 0 = no 1 = bldg stone 2 = hammer 3 = anvil
9
22. VENTSURF: -1 0 = flat 1
2
3 = very convex 4 = irregular 9
23. CVNTSIDE: -1 0 = round 1 = sl. def. 2 = defined 3 = very defined 9
24. CVNTEND: -1 0 = round 1 = sl. def. 2 = defined 3 = very defined 9
25. PRFSIDE: -1 0 = flat 1 = sl. convex 2 = convex
9
26. PRFEND: -1 0 = flat 1 = sl. convex 2 = convex
9
27. ANGSIDE: -1 0 = conv. 1 = vert. 2 = sl. div. 3 = div. 4 = v. div. 9
28. ANGEND: -1 0 = conv. 1 = vert. 2 = sl. div. 3 = div. 4 = v. div. 9
29. DORSPOL: -1 0 = unpol. 1
2
3
4 = v.polished 5 = worn/damaged 9
30. LATPOL: -1 0 = none 1 = yes
9
31. VENTPOL: -1 0 = unpol. 1
2
3
4 = v.polished 5 = worn/damaged 9
32. SUPPPOL: -1 0 = unpol. 1
2
3
4 = v.polished 5 = worn/damaged 9
Foot/Support Characteristics:
33. SUPPPRAB: -1 0 = no 1 = poss. present 2 = present 3 = tripod elements 4 = tetrapod
34. SLENGTH:
mm 35. SPERPS:
mm 36. SPARA:
mm
37. SSHAPE: -1 0 = circular 1 = oval 2 = D-shaped 3 = square 4 = rectangular 5 = sq/rect
38. SCORN: -1
0 = no
1 = yes
9
39. SSIDE: -1 0 = unk 1 = left 2 = right
9
40. SEND: -1 0 = unk
1 = proximal
2 = distal
9
41. SPRF: -1 0 = parallel sides 1 = slightly narrowing 2 = much narrowing
9
42. SBASE: -1 0 = very flat 1 = slightly convex 2 = convex 3 = worn/damaged
9
9
9
105
APPENDIX H
PRINCIPAL COMPONENTS ANALYSIS FOR APIZACO ARTIFACTS
Analysis based on variance-covariance matrix, scores from eigenvectors.
Eigenvalues and percentage of variance explained:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Eigenvalue %Variance Cum. %Var.
0.4236
53.0446
53.0446
0.1889
23.6607
76.7053
0.0886
11.097
87.8023
0.0352
4.4102
92.2125
0.0193
2.4161
94.6286
0.0106
1.3291
95.9577
0.0078
0.9728
96.9304
0.0052
0.6464
97.5768
0.0039
0.4911
98.0679
0.0033
0.4104
98.4783
0.0027
0.342
98.8203
0.0018
0.2277
99.048
0.0017
0.2084
99.2564
0.0014
0.1782
99.4346
0.0012
0.1464
99.581
0.001
0.1198
99.7008
0.0008
0.0989
99.7996
0.0004
0.0474
99.847
0.0003
0.0342
99.8812
0.0002
0.0267
99.9078
0.0002
0.0227
99.9305
0.0002
0.0192
99.9498
0.0001
0.0183
99.9681
0.0001
0.0129
99.981
0.0001
0.0091
99.9901
0
0.0051
99.9952
0
0.0029
99.9981
0
0.0019
100
106
Eigenvectors (largest to smallest):
La
Lu
Nd
Sm
Yb
Ce
Co
Cr
Eu
Fe
Hf
Rb
Sc
Sr
0.1842 -0.2292 -0.0516 -0.2829 0.0405 -0.0162 0.0717 -0.0354 0.0055 0.0372
-0.2026 -0.1590 -0.1287 0.0403 -0.1314 -0.1808 0.2970 -0.2904 0.5011 0.0151
0.1758 -0.1189 -0.1368 -0.1753 0.2662 0.3070 -0.0460 -0.0329
0.0228 0.0405 -0.2813 -0.0603 -0.1524 0.1437 -0.1057 0.0157 0.1908 -0.1113
-0.0305 -0.0411 0.2517 -0.2653 -0.1171 0.3181 0.2077 0.3674 0.1778 0.1502
-0.0327 -0.3393 -0.2656 -0.2096 -0.1261 -0.1982 -0.1882 0.0780
0.2145 -0.2201 0.0133 -0.2367 -0.0162 -0.1823 0.0527 -0.0254 -0.0365 0.0670
-0.1005 -0.2632 0.0884 0.1323 -0.0164 -0.0624 0.0342 -0.1161 -0.0415 0.2909
-0.0200 0.2829 0.0955 -0.1871 -0.6422 -0.2385 -0.0158 0.0515
0.2105 -0.1934 -0.0072 -0.2055 -0.0802 -0.1493 0.0254 0.0371 0.0275 0.0661
-0.0771 -0.1166 0.1418 -0.0064 0.0671 0.0320 -0.1238 0.1963 -0.2426 -0.0668
0.0703 0.1030 -0.2428 0.1279 0.2722 0.0678 0.2303 0.6746
0.0374 0.0484 -0.2692 -0.0830 -0.1780 0.1653 -0.1005 -0.0310 0.2211 -0.0579
-0.1078 -0.2337 0.1084 -0.3858 -0.0782 -0.1260 0.0550 -0.3338 -0.0054 -0.3880
0.0123 0.1509 0.1755 0.4352 -0.0654 -0.1708 -0.0629 0.0144
0.2115 -0.2444 -0.0296 -0.0898 0.1488 -0.1335 0.0846 -0.1858 -0.0924 -0.2017
0.0516 0.0921 0.2394 0.1681 0.0810 0.1283 -0.0378 0.0972 0.1318 -0.1472
-0.0139 -0.1169 0.5537 -0.0393 0.3142 -0.3604 -0.1879 0.0112
0.2271 0.1162 -0.0225 -0.0434 -0.0680 -0.1538 -0.0498 -0.1021 0.3093 -0.1382
0.1868 -0.1250 -0.4396 0.1031 0.0770 -0.4915 0.1149 0.2983 -0.0049 0.0527
-0.2419 -0.1024 -0.0865 0.0863 0.0882 -0.2695 0.0345 -0.0651
0.6723 0.1295 0.1912 0.5860 0.1573 -0.0484 0.1398 0.1079 0.0830 0.0515
-0.0964 -0.0393 0.0919 -0.1862 0.0250 0.0338 0.0318 -0.0224 0.0464 -0.0516
0.0677 0.0065 -0.0436 -0.0185 -0.0583 0.0715 -0.0771 -0.0004
0.2160 -0.1045 0.0153 -0.2637 -0.1123 -0.1626 0.0998 0.0289 -0.0547 -0.0096
-0.0050 -0.2001 0.1784 0.1338 0.1013 0.1622 -0.1844 0.0099 -0.2838 -0.2506
-0.1053 -0.2430 -0.3042 0.1284 -0.0075 0.1361 -0.0467 -0.5622
0.1181 0.0999 -0.0715 -0.0693 -0.1365 0.0625 -0.0095 -0.1862 -0.0484 -0.1159
0.0725 -0.0956 -0.1856 0.0628 -0.1357 0.0188 -0.1785 0.1917 -0.0157 -0.1182
-0.1409 -0.1591 0.3315 0.0109 -0.2788 0.5898 -0.3123 0.2456
0.0465 -0.0893 -0.2015 0.0295 0.0939 -0.0452 0.0199 -0.1190 -0.1750 -0.0231
0.0224 -0.1373 0.0621 -0.2157 -0.1132 0.0060 -0.2410 0.3382 0.2633 0.4493
0.0723 0.2560 0.0487 0.4160 0.1056 0.1448 0.1417 -0.2592
-0.1915 -0.4187 -0.2441 0.4484 -0.4607 -0.0839 0.4257 0.0209 -0.1486 -0.2343
-0.0433 -0.0112 -0.0521 0.0423 0.0374 -0.1582 0.0496 -0.0037 -0.0460 -0.0257
0.0449 -0.0469 -0.0653 -0.0237 -0.0355 -0.0068 -0.0254 0.0187
0.1664 0.0922 -0.0327 0.0591 -0.3331 0.1864 -0.0777 -0.0914 -0.0050 -0.0465
0.1608 -0.1084 0.0172 0.0803 -0.0199 0.1628 -0.2549 -0.0976 0.3016 -0.1400
-0.2076 0.0347 0.0846 -0.2978 0.0064 -0.0272 0.6311 -0.0382
0.1011 -0.1021 0.3059 -0.2012 -0.0173 -0.0786 0.0289 -0.3015 -0.2593 -0.3833
0.1513 0.2928 -0.0981 -0.5394 0.0026 0.0086 0.2239 -0.0197 -0.1260 -0.0606
0.0026 0.0585 -0.0783 -0.0735 -0.1018 0.0496 0.1561 -0.0370
107
Ta
Tb
Th
Zn
Zr
Al
Ba
Ca
Dy
K
Mn
Na
Ti
V
0.0837 0.0928 -0.6116 -0.0091 0.4522 0.1258 0.2218 -0.2614 0.0563 -0.1300
-0.0670 0.0537 -0.2271 0.0289 0.2041 0.1412 -0.0508 -0.1119 -0.2123 -0.0337
0.0617 0.0803 -0.1110 -0.1756 -0.0331 0.0270 0.1198 -0.0002
0.1737 -0.1048 -0.1543 -0.1662 -0.1250 -0.1540 0.0907 0.4464 0.0619 0.0884
-0.2023 0.4662 -0.3719 -0.0953 -0.1920 0.2564 -0.1039 -0.0092 0.0654 -0.0161
-0.2930 0.1556 0.0654 0.0529 0.0200 -0.0576 -0.0511 -0.0420
0.0566 -0.5334 -0.0840 0.2426 0.1745 0.0708 -0.7076 -0.0184 0.0461 -0.1329
-0.1097 0.1109 -0.0297 0.1051 -0.0184 -0.0454 -0.0142 -0.0068 -0.0745 -0.0624
-0.0995 -0.0376 -0.0739 0.0256 -0.0907 0.0994 0.0621 -0.0480
0.1064 0.0070 0.0091 -0.0390 -0.0762 0.1573 0.0137 -0.0729 0.0382 0.0848
-0.2224 0.0832 -0.0743 0.0051 -0.5789 -0.1805 -0.1457 0.1359 -0.3470 0.0117
0.4541 -0.1788 0.1566 -0.1564 0.0429 -0.1273 0.1674 -0.1384
0.0735 -0.0963 -0.2049 -0.0169 0.1309 -0.0552 -0.0806 0.4531 -0.2285 0.0502
0.6733 -0.1952 -0.1351 -0.0671 -0.1214 0.0447 0.1224 0.0172 -0.0358 -0.1458
0.2800 -0.0224 0.0564 -0.0548 -0.0397 -0.0199 0.0178 0.0159
-0.0349 0.0232 0.0017 -0.0436 -0.0127 0.1049 -0.0191 -0.0051 -0.0600 0.0280
-0.0890 0.0696 0.0672 0.0673 0.0422 -0.1641 -0.0220 0.4454 0.1843 -0.4867
0.1405 0.5491 -0.1605 -0.2480 -0.0397 0.0033 -0.1840 -0.1276
0.0852 -0.3239 0.2472 -0.1113 0.1171 0.7785 0.2838 0.1322 0.0916 -0.0261
0.1257 -0.0532 -0.0616 0.0186 0.0483 -0.0167 -0.0499 0.0472 -0.0545 0.1030
-0.1597 0.0282 -0.0316 0.0893 0.0156 -0.0478 -0.0767 0.0072
0.1227 0.0423 0.0740 -0.0787 -0.1700 0.0480 -0.0720 -0.0583 0.1001 -0.1950
0.1107 0.2797 -0.1482 0.1986 0.2192 0.0947 -0.3163 -0.1287 0.2648 0.0345
0.5412 -0.0898 -0.2004 0.2570 -0.2055 -0.1332 -0.1153 0.0798
0.1315 -0.0354 -0.1977 -0.1268 -0.1985 0.0968 -0.0920 0.1341 0.0039 0.3112
0.0108 0.2593 0.1761 -0.2531 0.5313 -0.3535 -0.0564 0.0453 -0.0846 0.1533
0.0955 -0.1341 0.2339 -0.1816 0.0041 0.1551 0.0283 -0.0946
-0.0648 -0.2998 0.0340 0.0836 -0.0115 -0.1126 0.1286 -0.4412 0.3152 0.6160
0.2829 0.1276 -0.0866 -0.0748 -0.0666 0.1816 0.0744 0.0480 0.0654 -0.1392
0.0213 -0.0166 -0.0164 0.0768 -0.0927 0.0081 0.0157 -0.0295
0.1416 0.0919 -0.0772 -0.0308 -0.1956 0.0672 0.0076 0.0219 0.2744 -0.1662
0.1327 0.2147 0.2230 0.3616 -0.0429 0.1359 0.5343 0.0396 -0.1635 0.1318
0.1040 0.2630 0.1300 0.1655 0.0317 0.2526 0.1473 -0.1094
-0.0265 0.0316 -0.0012 -0.0330 0.1767 0.0649 0.1183 0.0991 -0.2752 0.1214
-0.2677 0.0660 -0.0428 0.1229 0.1142 -0.0302 0.2974 0.2665 0.1800 -0.2515
0.0144 -0.3213 0.0903 0.3335 -0.3319 -0.0504 0.3833 0.0548
0.1965 0.1306 -0.2178 0.0011 -0.0131 0.1145 -0.0001 -0.1698 -0.3900 0.1605
0.2041 0.3327 0.2806 0.1775 -0.2965 -0.3001 -0.0163 -0.1776 0.0361 0.0232
-0.2668 -0.0252 -0.2768 0.1193 -0.0169 -0.1003 -0.1325 0.1103
0.1631 0.0792 -0.0099 0.0604 -0.3101 0.1908 -0.2292 -0.1956 -0.4347 0.2400
-0.1404 -0.1901 -0.3537 0.0598 0.1770 0.2864 0.2373 0.0087 -0.1505 0.0926
0.0615 0.1012 0.0138 0.0429 0.1861 -0.1627 -0.1739 -0.0244
108
Scaled Factor Loading Matrix (largest to smallest component):
La
Lu
Nd
Sm
Yb
Ce
Co
Cr
Eu
Fe
Hf
Rb
Sc
Sr
0.1199 -0.0996 -0.0153 -0.0531 0.0056 -0.0017 0.0063 -0.0025 0.0003 0.0021
-0.0106 -0.0068 -0.0053 0.0015 -0.0045 -0.0056 0.0083 -0.0056 0.0083 0.0002
0.0024 -0.0015 -0.0017 -0.0018 0.0023 0.0020 -0.0002 -0.0001
0.0149 0.0176 -0.0837 -0.0113 -0.0212 0.0148 -0.0093 0.0011 0.0120 -0.0064
-0.0016 -0.0018 0.0103 -0.0100 -0.0040 0.0098 0.0058 0.0071 0.0029 0.0022
-0.0004 -0.0042 -0.0032 -0.0021 -0.0011 -0.0013 -0.0009 0.0003
0.1396 -0.0957 0.0040 -0.0444 -0.0023 -0.0188 0.0046 -0.0018 -0.0023 0.0038
-0.0053 -0.0112 0.0036 0.0050 -0.0006 -0.0019 0.0010 -0.0023 -0.0007 0.0042
-0.0003 0.0035 0.0012 -0.0019 -0.0055 -0.0015 -0.0001 0.0002
0.1370 -0.0840 -0.0021 -0.0386 -0.0111 -0.0154 0.0022 0.0027 0.0017 0.0038
-0.0040 -0.0050 0.0058 -0.0002 0.0023 0.0010 -0.0035 0.0038 -0.0040 -0.0010
0.0009 0.0013 -0.0029 0.0013 0.0023 0.0004 0.0011 0.0026
0.0244 0.0211 -0.0801 -0.0156 -0.0247 0.0170 -0.0089 -0.0022 0.0138 -0.0033
-0.0056 -0.0100 0.0044 -0.0146 -0.0027 -0.0039 0.0015 -0.0065 -0.0001 -0.0057
0.0002 0.0019 0.0021 0.0044 -0.0006 -0.0011 -0.0003 0.0001
0.1377 -0.1063 -0.0088 -0.0168 0.0207 -0.0138 0.0075 -0.0133 -0.0058 -0.0115
0.0027 0.0039 0.0098 0.0063 0.0028 0.0040 -0.0011 0.0019 0.0022 -0.0021
-0.0002 -0.0014 0.0067 -0.0004 0.0027 -0.0023 -0.0009 0.0000
0.1478 0.0505 -0.0067 -0.0081 -0.0094 -0.0158 -0.0044 -0.0073 0.0194 -0.0079
0.0098 -0.0053 -0.0179 0.0039 0.0026 -0.0152 0.0032 0.0058 -0.0001 0.0008
-0.0033 -0.0013 -0.0010 0.0009 0.0008 -0.0017 0.0002 -0.0003
0.4376 0.0563 0.0569 0.1100 0.0219 -0.0050 0.0123 0.0078 0.0052 0.0029
-0.0050 -0.0017 0.0038 -0.0070 0.0009 0.0010 0.0009 -0.0004 0.0008 -0.0008
0.0009 0.0001 -0.0005 -0.0002 -0.0005 0.0005 -0.0004 0.0000
0.1406 -0.0454 0.0046 -0.0495 -0.0156 -0.0168 0.0088 0.0021 -0.0034 -0.0006
-0.0003 -0.0085 0.0073 0.0050 0.0035 0.0050 -0.0052 0.0002 -0.0047 -0.0037
-0.0014 -0.0030 -0.0037 0.0013 -0.0001 0.0009 -0.0002 -0.0022
0.0769 0.0434 -0.0213 -0.0130 -0.0190 0.0064 -0.0008 -0.0134 -0.0030 -0.0066
0.0038 -0.0041 -0.0076 0.0024 -0.0046 0.0006 -0.0050 0.0037 -0.0003 -0.0017
-0.0019 -0.0020 0.0040 0.0001 -0.0024 0.0038 -0.0015 0.0010
0.0303 -0.0388 -0.0600 0.0055 0.0130 -0.0047 0.0018 -0.0086 -0.0110 -0.0013
0.0012 -0.0059 0.0025 -0.0081 -0.0039 0.0002 -0.0068 0.0066 0.0043 0.0066
0.0010 0.0032 0.0006 0.0042 0.0009 0.0009 0.0007 -0.0010
-0.1246 -0.1820 -0.0727 0.0841 -0.0640 -0.0086 0.0375 0.0015 -0.0093 -0.0134
-0.0023 -0.0005 -0.0021 0.0016 0.0013 -0.0049 0.0014 -0.0001 -0.0008 -0.0004
0.0006 -0.0006 -0.0008 -0.0002 -0.0003 0.0000 -0.0001 0.0001
0.1083 0.0401 -0.0097 0.0111 -0.0463 0.0192 -0.0068 -0.0066 -0.0003 -0.0027
0.0084 -0.0046 0.0007 0.0030 -0.0007 0.0050 -0.0072 -0.0019 0.0050 -0.0020
-0.0028 0.0004 0.0010 -0.0030 0.0001 -0.0002 0.0030 -0.0001
0.0658 -0.0444 0.0911 -0.0377 -0.0024 -0.0081 0.0025 -0.0217 -0.0162 -0.0219
0.0079 0.0125 -0.0040 -0.0203 0.0001 0.0003 0.0063 -0.0004 -0.0021 -0.0009
0.0000 0.0007 -0.0009 -0.0007 -0.0009 0.0003 0.0008 -0.0001
109
Ta
Tb
Th
Zn
Zr
Al
Ba
Ca
Dy
K
Mn
Na
Ti
V
0.0545 0.0403 -0.1821 -0.0017 0.0628 0.0130 0.0195 -0.0188 0.0035 -0.0074
-0.0035 0.0023 -0.0093 0.0011 0.0070 0.0044 -0.0014 -0.0022 -0.0035 -0.0005
0.0008 0.0010 -0.0013 -0.0018 -0.0003 0.0002 0.0006 0.0000
0.1130 -0.0456 -0.0459 -0.0312 -0.0174 -0.0159 0.0080 0.0321 0.0039 0.0051
-0.0106 0.0199 -0.0152 -0.0036 -0.0066 0.0079 -0.0029 -0.0002 0.0011 -0.0002
-0.0039 0.0019 0.0008 0.0005 0.0002 -0.0004 -0.0002 -0.0002
0.0368 -0.2318 -0.0250 0.0455 0.0242 0.0073 -0.0624 -0.0013 0.0029 -0.0076
-0.0057 0.0047 -0.0012 0.0040 -0.0006 -0.0014 -0.0004 -0.0001 -0.0012 -0.0009
-0.0013 -0.0005 -0.0009 0.0003 -0.0008 0.0006 0.0003 -0.0002
0.0693 0.0031 0.0027 -0.0073 -0.0106 0.0162 0.0012 -0.0052 0.0024 0.0049
-0.0116 0.0035 -0.0030 0.0002 -0.0198 -0.0056 -0.0041 0.0026 -0.0057 0.0002
0.0061 -0.0022 0.0019 -0.0016 0.0004 -0.0008 0.0008 -0.0005
0.0479 -0.0419 -0.0610 -0.0032 0.0182 -0.0057 -0.0071 0.0326 -0.0143 0.0029
0.0352 -0.0083 -0.0055 -0.0025 -0.0041 0.0014 0.0034 0.0003 -0.0006 -0.0021
0.0038 -0.0003 0.0007 -0.0006 -0.0003 -0.0001 0.0001 0.0001
-0.0227 0.0101 0.0005 -0.0082 -0.0018 0.0108 -0.0017 -0.0004 -0.0038 0.0016
-0.0047 0.0030 0.0027 0.0025 0.0014 -0.0051 -0.0006 0.0087 0.0030 -0.0071
0.0019 0.0068 -0.0019 -0.0025 -0.0003 0.0000 -0.0009 -0.0005
0.0554 -0.1408 0.0736 -0.0209 0.0163 0.0802 0.0250 0.0095 0.0057 -0.0015
0.0066 -0.0023 -0.0025 0.0007 0.0017 -0.0005 -0.0014 0.0009 -0.0009 0.0015
-0.0021 0.0003 -0.0004 0.0009 0.0001 -0.0003 -0.0004 0.0000
0.0799 0.0184 0.0220 -0.0148 -0.0236 0.0049 -0.0063 -0.0042 0.0063 -0.0112
0.0058 0.0119 -0.0060 0.0075 0.0075 0.0029 -0.0089 -0.0025 0.0044 0.0005
0.0073 -0.0011 -0.0024 0.0026 -0.0018 -0.0008 -0.0006 0.0003
0.0856 -0.0154 -0.0588 -0.0238 -0.0276 0.0100 -0.0081 0.0096 0.0002 0.0178
0.0006 0.0111 0.0072 -0.0095 0.0182 -0.0109 -0.0016 0.0009 -0.0014 0.0022
0.0013 -0.0017 0.0028 -0.0018 0.0000 0.0010 0.0001 -0.0004
-0.0422 -0.1303 0.0101 0.0157 -0.0016 -0.0116 0.0113 -0.0317 0.0197 0.0353
0.0148 0.0054 -0.0035 -0.0028 -0.0023 0.0056 0.0021 0.0009 0.0011 -0.0020
0.0003 -0.0002 -0.0002 0.0008 -0.0008 0.0001 0.0001 -0.0001
0.0922 0.0399 -0.0230 -0.0058 -0.0272 0.0069 0.0007 0.0016 0.0172 -0.0095
0.0069 0.0092 0.0091 0.0136 -0.0015 0.0042 0.0150 0.0008 -0.0027 0.0019
0.0014 0.0033 0.0016 0.0017 0.0003 0.0016 0.0007 -0.0004
-0.0172 0.0137 -0.0003 -0.0062 0.0245 0.0067 0.0104 0.0071 -0.0172 0.0069
-0.0140 0.0028 -0.0017 0.0046 0.0039 -0.0009 0.0084 0.0052 0.0030 -0.0037
0.0002 -0.0040 0.0011 0.0034 -0.0028 -0.0003 0.0018 0.0002
0.1279 0.0568 -0.0648 0.0002 -0.0018 0.0118 0.0000 -0.0122 -0.0244 0.0092
0.0107 0.0142 0.0114 0.0067 -0.0101 -0.0093 -0.0005 -0.0035 0.0006 0.0003
-0.0036 -0.0003 -0.0033 0.0012 -0.0001 -0.0006 -0.0006 0.0004
0.1062 0.0344 -0.0029 0.0113 -0.0431 0.0197 -0.0202 -0.0141 -0.0272 0.0137
-0.0073 -0.0081 -0.0144 0.0023 0.0061 0.0089 0.0067 0.0002 -0.0025 0.0014
0.0008 0.0013 0.0002 0.0004 0.0016 -0.0010 -0.0008 -0.0001
110
Hierarchical Clustering Diagram of Apizaco Artifacts
Table of Artifacts Grouped by Possible Source.
Source Group Number Grinding Tool Number
1
GT 40
GT 154
2
GT 2
GT 120
3
GT 55
GT 109
4
GT 55
GT 109
GT 94
5
GT 2
GT 120
GT 55
111
Source Group Number Grinding Tool Number
GT 109
6
GT 40
GT 154
GT 2
GT 120
GT 55
GT 109
7
GT 133
GT 145
8
GT 81
9
GT 133
GT 145
GT 81
10
GT 11
GT 41
11
GT 11
GT 41
GT 16
12
GT 48
GT 111
13
GT 48
GT 111
GT 144
14
GT 11
GT 41
GT 16
GT 48
GT 111
GT 144
15
GT 47
GT 82
16
GT 47
GT 82
GT 114
17
GT 47
GT 82
GT 114
GT 95
18
GT 47
GT 82
GT 114
GT 95
GT 10
112
Source Group Number Grinding Tool Number
19
GT 47
GT 82
GT 114
GT 95
GT 10
GT 155
20
GT 38
GT 39
21
GT 38
GT 39
GT 37
22
GT 38
GT 39
GT 37
GT 15
23
GT 117
GT 147
24
GT 88
GT 93
25
GT 117
GT 147
GT 88
GT 93
26
GT 22
GT 127
27
GT 22
GT 127
GT 21
28
GT 96
29
GT 58
30
GT 132
31
GT 135
32
GT 117
GT 147
GT 88
GT 93
GT 22
GT 127
GT 21
113
APPENDIX I
TLACHINOLPAN SOURCE ASSIGNMENT ANALYSIS
I. High Chromium Group:
A. Principal Components Analysis of the High Chromium Source Fingerprints:
analysis based on variance-covariance matrix
Eigenvalues and Percentage of Variance Explained:
1
2
3
4
5
Eigenvalue %Variance
0.2245
65.2338
0.0595
17.2753
0.0187
5.4379
0.0157
4.5526
0.0056
1.6323
Principal Components (largest to smallest):
FE
AL
CA
NA
LA
LU
ND
SM
YB
CE
CR
EU
HF
TA
TB
TH
DY
MN
TI
V
0.1170
-0.0135
0.0731
-0.0861
-0.3939
-0.0488
-0.4961
-0.3067
-0.1012
-0.4009
0.1138
-0.2259
-0.1905
-0.0336
-0.1531
-0.3822
-0.1322
0.0621
0.0313
0.1069
0.0751
0.0518
-0.0462
0.0636
-0.0970
0.2249
-0.1704
-0.0303
0.2168
-0.0465
-0.6196
0.0141
0.2738
0.4640
0.1048
-0.1298
0.1287
0.0620
0.3460
-0.0631
0.0336
0.0561
0.0674
-0.0034
0.1650
0.3762
-0.2338
-0.0245
0.4858
0.0072
0.5790
-0.0300
0.1727
0.0316
0.1830
0.0515
0.1794
0.2273
0.1216
0.1711
-0.2035
0.0988
0.1054
-0.0253
0.0601
0.1629
-0.0001
0.0503
0.2753
-0.0768
-0.3348
0.0411
-0.0121
-0.6601
0.2745
-0.3838
0.1020
-0.1065
-0.1669
0.0274
-0.1807
0.0736
0.2987
0.0580
0.0136
0.0546
-0.1358
0.0163
0.2238
0.2170
-0.1192
-0.0240
0.2174
-0.1012
-0.7859
0.0496
-0.0619
0.1544
-0.1600
-0.0687
114
B. Source Assignment Analysis Using First Two PC’s: values are probabilities
that the artifact sample belongs to the fingerprint source.
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
HS028
HS029
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
HS118
HS119
02B
0.1
0.0
0.3
0.0
0.0
0.0
0.0
0.7
0.0
0.0
1.4
0.0
0.0
0.0
0.0
0.0
0.0
86.1
67.5
0.0
0.9
5.2
0.0
14.4
1.4
0.0
0.0
0.0
0.0
4.8
0.9
0.0
0.0
0.0
0.0
0.0
67.2
0.0
0.0
05A
0.0
0.0
0.0
0.0
0.0
0.1
0.2
0.0
0.0
0.7
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
15.7
0.0
13C
56.3
5.8
36.8
76.5
14.9
0.0
0.0
0.0
0.2
0.0
13.9
5.1
0.0
0.0
0.1
0.3
1.1
1.4
0.6
40.8
23.8
0.0
80.0
5.1
18.4
0.0
0.2
0.0
4.3
0.2
23.4
54.2
3.9
0.0
51.3
1.8
0.8
0.0
32.6
14A
76.2
0.4
45.7
71.5
1.6
0.0
0.0
0.0
3.9
0.0
22.6
0.1
0.9
0.0
2.2
0.6
1.6
1.0
0.4
14.2
27.1
0.1
22.1
3.0
14.7
0.0
0.3
0.9
0.3
0.4
25.1
67.0
21.5
0.8
4.9
0.4
0.5
0.0
3.6
28A
0.0
0.1
0.0
0.2
0.0
0.0
0.0
0.0
93.1
0.0
0.0
0.8
10.9
0.0
55.7
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.0
0.0
11.1
0.1
0.0
0.0
0.6
18.4
6.9
3.8
0.0
0.0
0.0
0.0
61A
0.0
0.1
0.0
0.0
0.0
11.0
1.1
0.0
0.0
0.0
0.0
0.0
0.0
18.5
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.6
0.1
0.0
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.0
65A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.6
0.0
0.0
0.0
5.5
0.0
3.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
9.5
0.0
0.0
0.0
0.0
0.1
3.9
0.0
0.0
0.0
0.0
0.0
115
ANID
HS120
02B
0.0
05A
0.0
13C
26.0
14A
88.2
28A
0.5
61A
0.0
65A
0.0
C. Source Assignment Analysis Using First Three PC’s:
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
HS028
HS029
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
02B
0.2
0.0
0.6
0.1
0.0
0.0
0.0
0.3
0.0
0.0
0.1
0.0
0.0
0.0
0.0
0.0
0.1
2.0
0.9
0.1
1.1
0.5
0.1
2.6
4.7
0.0
0.0
0.0
0.0
0.2
3.2
0.1
0.1
0.0
0.0
0.0
32.4
05A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
13C
0.0
12.6
36.3
32.9
0.2
0.0
0.0
0.0
0.7
0.0
0.0
2.2
0.1
0.0
0.4
0.0
0.0
0.0
0.0
19.9
28.8
0.0
68.4
0.0
0.3
0.0
0.0
0.1
0.1
0.0
0.4
46.3
0.0
0.1
10.1
0.0
0.0
14A
0.0
1.4
69.4
19.2
0.0
0.0
0.0
0.0
1.2
0.0
0.0
0.1
0.5
0.0
2.1
0.0
0.0
0.0
0.0
4.9
45.2
0.0
30.8
0.0
0.2
0.0
0.0
2.0
0.0
0.0
0.3
68.2
0.0
0.7
0.6
0.0
0.0
28A
0.0
0.3
0.1
0.8
0.0
0.0
0.0
0.0
0.9
0.0
0.0
0.0
0.7
0.0
8.7
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.2
0.0
0.0
0.0
0.0
21.4
0.0
0.0
0.0
2.2
0.0
2.4
0.1
0.0
0.0
61A
0.0
0.3
0.0
0.0
0.0
1.7
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.8
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.9
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
65A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.0
0.0
0.0
0.0
3.0
0.0
5.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
20.7
0.0
0.0
0.0
0.0
0.0
4.5
0.0
0.0
0.0
116
ANID
HS118
HS119
HS120
02B
0.0
0.0
0.1
05A
0.1
0.0
0.0
13C
0.0
33.4
43.1
14A
0.0
4.7
40.5
28A
0.0
0.3
0.3
61A
0.0
0.0
0.0
65A
0.0
0.0
0.0
61A
0.0
0.9
0.0
0.0
0.0
4.0
0.3
0.0
0.0
0.0
0.0
0.0
0.0
2.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
5.9
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
65A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.0
0.1
0.0
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
D. Source Assignment Analysis Using First Four PC’s:
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
HS028
HS029
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
02B
0.6
0.0
1.6
0.1
0.1
0.0
0.0
0.9
0.0
0.0
0.3
0.0
0.0
0.0
0.0
0.2
0.3
2.4
2.9
0.1
2.9
1.8
0.3
2.1
10.5
0.0
0.1
0.0
0.0
0.6
8.8
0.1
0.1
0.0
0.0
05A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
13C
0.0
8.6
5.7
46.1
0.2
0.0
0.0
0.0
0.1
0.0
0.0
3.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
12.5
10.0
0.0
16.7
0.0
0.7
0.0
0.0
0.0
0.1
0.0
0.5
50.9
0.1
0.0
17.8
14A
0.0
0.1
0.1
11.2
0.1
0.0
0.0
0.0
2.4
0.0
0.0
0.1
0.7
0.0
1.7
0.0
0.0
0.0
0.0
10.6
0.2
0.0
0.1
0.0
0.6
0.0
0.0
0.4
0.0
0.0
0.5
25.5
0.2
0.6
1.0
28A
0.0
0.0
0.0
2.3
0.0
0.0
0.0
0.0
2.4
0.0
0.0
0.1
2.3
0.0
19.3
0.0
0.0
0.0
0.0
0.5
0.0
0.0
0.1
0.0
0.1
0.0
0.0
9.0
0.0
0.0
0.1
3.5
0.0
7.0
0.5
117
ANID
HS105
HS107
HS118
HS119
HS120
02B
0.0
40.1
0.0
0.1
0.2
05A
0.0
0.0
0.1
0.0
0.0
13C
0.0
0.0
0.1
31.2
52.1
14A
0.0
0.1
0.1
0.2
7.6
28A
0.0
0.0
0.0
0.1
0.3
61A
0.0
0.0
0.0
0.1
0.0
65A
0.0
0.0
0.0
0.0
0.1
E. Summary of Source Assignment Analyses For High Chromium Samples:
Best Fitting Source
(minimum 5% fit)
ANID
HS004
HS005
HS007
HS014
HS021
HS036
HS065
HS068
HS070
HS084
HS088
HS099
HS104
HS107
HS119
HS120
PC 1-2
13C
14A
13C
61A
28A
28A
13C
14A
13C
UNK
28A
14A
13C
02B
13C
14A
PC 1-3
13C
14A
13C
UNK
UNK
28A
13C
14A
13C
UNK
28A
14A
13C
02B
13C
13C
PC 1-4
13C
13C
13C
UNK
UNK
28A
13C
13C
13C
61A
28A
13C
13C
02B
13C
13C
Counts of assignments at
1% probability or better
02B 05A
0
0
1
0
0
0
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
0
0
0
3
0
0
0
0
0
13C 14A 28A 61A 65A
3
1
0
0
0
3
2
0
0
0
3
3
1
0
0
0
0
0
3
0
0
3
2
0
2
0
3
3
0
2
3
3
0
0
0
3
2
0
0
0
3
2
0
0
0
0
0
0
2
0
0
1
3
0
2
3
3
2
0
0
3
2
1
0
0
0
0
0
0
0
3
2
0
0
0
3
3
0
0
0
II. Middle Chromium Group
A. Principal Components Analysis of the Middle Chromium Source Fingerprints:
analysis based on variance-covariance matrix
Eigenvalues and Percentage of Variance Explained:
1
2
3
4
5
Eigenvalue %Variance
0.1061
40.5470
0.0962
36.7774
0.0279
10.6564
0.0080
3.0727
0.0046
1.7761
118
Principal Components (largest to smallest):
FE
AL
CA
NA
LA
LU
ND
SM
YB
CE
CR
EU
HF
TA
TB
TH
DY
MN
TI
V
0.2767
0.0238
0.2546
-0.0237
0.0107
0.1439
0.0409
0.1098
0.1730
0.0342
0.3442
0.1903
0.0395
0.1190
0.1922
-0.5134
0.1389
0.3008
0.3841
0.2522
0.0111
0.0707
0.1717
-0.0086
-0.3637
-0.0855
-0.3149
-0.2181
-0.0860
-0.3373
-0.2962
-0.0960
-0.2026
-0.4472
-0.1265
-0.4191
-0.1192
-0.0106
0.0327
0.1132
-0.0578
-0.0509
-0.1347
0.0885
-0.2189
-0.1832
-0.0797
-0.1535
-0.2025
-0.1141
0.8311
-0.1461
0.0908
-0.1135
-0.2037
0.0642
-0.1194
-0.0913
0.0003
0.0358
-0.0584
0.0074
0.0395
-0.0908
-0.0131
-0.0101
0.3871
0.1013
0.0051
-0.1182
0.1208
0.0169
-0.0858
-0.5833
0.5548
0.1720
0.1800
-0.0004
-0.2113
0.1884
0.0680
0.0234
0.1450
-0.3012
-0.0108
0.2084
-0.5965
0.0843
0.1242
-0.0716
0.1143
-0.0424
-0.2509
0.0803
0.0074
0.4505
0.1832
0.1733
-0.1316
0.2965
B. Source Assignment Analysis Using First Two PC’s: values are probabilities
that the artifact sample belongs to the fingerprint source.
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
HS028
HS029
02A
0.9
0.0
0.0
0.0
41.7
1.2
0.1
0.5
0.0
0.0
0.0
90.5
0.0
02B
0.0
21.4
78.2
12.9
0.1
0.0
0.0
0.1
0.0
2.6
0.0
0.2
0.0
05B
56.6
1.9
1.0
1.4
11.0
4.3
2.3
3.4
1.3
2.0
14.9
13.3
1.5
28C
0.2
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.5
0.0
0.4
1.2
0.9
62B
75.5
0.0
0.0
0.0
0.6
0.2
0.0
0.1
0.0
0.0
2.3
0.0
0.0
119
ANID
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
HS118
HS119
HS120
02A
0.6
0.0
13.4
1.5
32.6
60.0
0.0
0.0
60.2
0.0
67.8
2.1
0.0
6.3
0.6
13.1
0.2
4.1
0.0
35.3
0.0
85.7
27.9
0.1
16.3
0.0
0.0
02B
0.0
0.0
0.0
0.0
0.0
0.1
33.5
75.8
0.9
83.4
0.1
1.0
0.1
0.0
0.0
0.0
0.0
1.0
5.6
0.1
0.0
0.3
0.1
10.6
2.5
28.8
5.4
05B
3.8
1.5
19.7
61.7
23.7
12.8
1.1
1.1
7.1
1.3
12.4
4.0
1.3
35.6
2.3
34.4
85.4
4.5
1.3
14.8
1.6
11.0
8.7
2.1
5.2
1.9
1.1
28C
0.0
0.8
0.0
0.0
0.1
0.1
0.0
0.0
1.6
0.0
0.1
0.0
0.0
0.0
3.0
0.1
0.0
0.0
0.1
19.1
1.0
0.5
0.0
0.0
0.4
0.0
0.0
62B
0.1
0.0
9.9
14.5
6.5
0.4
0.0
0.0
0.0
0.0
0.2
0.0
0.0
21.7
0.0
34.4
0.6
0.0
0.0
0.0
0.0
0.0
0.3
0.0
0.0
0.0
0.0
C. Source Assignment Analysis Using First Three PC’s:
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
02A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
02B
0.0
0.0
0.0
0.4
0.0
0.0
0.0
0.2
0.2
0.0
0.0
05B
18.8
1.2
1.4
3.5
2.6
1.1
0.8
11.9
8.2
0.8
9.3
28C
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.0
62B
90.8
0.0
0.0
0.0
1.2
0.3
0.1
0.1
0.0
0.0
2.5
120
ANID
HS028
HS029
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
HS118
HS119
HS120
02A
0.0
0.0
0.0
0.0
0.0
0.0
39.8
23.5
0.0
0.0
1.5
0.0
84.3
0.2
0.0
0.0
0.3
0.0
0.0
0.1
0.0
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.0
02B
0.0
0.1
0.0
0.1
0.0
0.0
0.1
0.2
3.5
0.0
0.0
0.0
0.5
0.0
0.0
0.0
0.1
0.0
0.0
0.0
0.5
0.2
0.1
0.0
0.0
22.8
0.0
0.0
0.7
05B
2.9
8.6
1.0
8.9
2.9
4.8
47.1
20.0
3.2
1.5
5.3
1.3
28.6
3.6
0.8
2.8
7.8
2.1
13.5
3.8
3.7
29.9
8.7
6.7
2.3
6.6
1.7
1.6
3.3
28C
0.0
0.0
0.0
0.0
0.0
0.0
0.5
0.4
0.0
0.0
5.0
0.0
0.8
0.0
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.0
62B
0.1
0.0
0.2
0.0
18.6
28.5
3.8
0.3
0.0
0.0
0.0
0.0
0.3
0.1
0.0
25.1
0.0
7.8
1.5
0.1
0.0
0.1
0.0
0.2
0.7
0.0
0.0
0.0
0.0
D. Source Assignment Analysis Using First Four PC’s:
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
02A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
02B
0.0
0.0
0.0
0.2
0.0
0.0
0.0
0.7
0.0
05B
1.6
0.3
0.2
0.4
0.6
0.7
0.9
0.6
1.2
28C
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
62B
45.7
0.0
0.0
0.0
3.3
0.4
0.0
0.1
0.0
121
ANID
HS026
HS027
HS028
HS029
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
HS118
HS119
HS120
02A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
22.9
37.5
0.0
0.0
0.0
0.0
45.0
0.5
0.0
0.0
0.9
0.0
0.0
0.3
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
02B
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.6
0.7
0.1
0.0
0.1
0.0
0.8
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.2
0.2
0.0
0.0
0.0
32.5
0.0
0.0
0.3
05B
1.0
0.6
1.4
6.1
0.6
1.9
0.7
0.9
2.1
8.2
0.5
0.2
1.7
0.2
9.4
0.7
0.3
1.0
0.9
1.1
1.7
0.5
0.4
2.0
7.8
2.3
0.7
0.4
2.8
0.4
0.4
28C
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.1
0.1
0.0
7.0
0.0
0.1
0.1
0.0
0.0
0.0
0.0
0.0
0.1
0.0
0.2
0.0
0.0
0.0
0.4
0.0
0.0
0.0
62B
0.0
4.1
0.2
0.0
0.4
0.0
31.9
29.1
2.0
0.5
0.0
0.0
0.0
0.0
0.9
0.3
0.0
41.0
0.0
8.4
1.6
0.3
0.0
0.2
0.0
0.5
1.8
0.0
0.0
0.0
0.0
122
E. Summary of Source Assignment Analyses For Middle Chromium Samples:
Best Fitting Source
(minimum 5% fit)
ANID
HS003
HS015
HS026
HS028
HS029
HS039
HS042
HS063
HS064
HS069
HS072
HS085
HS089
HS097
HS103
HS107
PC 1-2
62B
UNK
UNK
02A
UNK
05B
05B
02A
02A
02A
02A
05B
05B
05B
UNK
02B
PC 1-3
62B
UNK
UNK
UNK
05B
62B
62B
05B
02A
05B
02A
62B
62B
05B
05B
02B
PC 1-4
62B
UNK
UNK
UNK
05B
62B
62B
02A
02A
28C
02A
62B
62B
UNK
05B
02B
Counts of assignments at
1% probability or better
02A 02B 05B 28C 62B
0
0
0
3
3
0
0
1
0
0
0
1
1
0
0
1
0
3
1
0
0
0
3
0
0
1
0
2
0
3
1
0
2
0
3
3
0
3
0
3
3
0
3
0
0
2
0
3
3
0
3
0
3
0
0
1
0
2
0
3
1
0
3
0
3
0
0
3
0
2
0
0
3
1
0
0
3
2
0
0
III. Low Chromium Group
A. Principal Components Analysis of the Low Chromium Source Fingerprints:
analysis based on variance-covariance matrix.
Eigenvalues and Percentage of Variance Explained:
1
2
3
4
5
Eigenvalue %Variance
0.2875
60.1392
0.0951
19.9060
0.0321
6.7242
0.0218
4.5691
0.0111
2.3311
123
Principal Components (largest to smallest):
FE
AL
CA
NA
LA
LU
ND
SM
YB
CE
CR
EU
HF
TA
TB
TH
DY
MN
TI
V
0.2478 0.2177 0.0031 0.0541 0.1308
0.0721 0.0163 0.0021 -0.0719 -0.0334
0.3171 0.0788 -0.0241 -0.0582 -0.1496
0.0619 0.1232 -0.0906 -0.1845 0.0898
-0.2016 0.2913 -0.0720 0.0824 -0.0041
-0.0454 0.1785 0.2678 0.0685 -0.2038
-0.1457 0.3131 0.0183 0.1848 0.0549
-0.1106 0.2172 0.0919 0.1599 -0.0017
-0.0393 0.1910 0.2833 0.1052 -0.2157
-0.1592 0.2607 -0.1120 0.0141 0.1666
0.2313 -0.0253 -0.4801 0.7617 0.1255
-0.0012 0.2370 0.1908 0.1649 0.1608
-0.0461 0.1761 -0.0866 -0.1130 0.3001
-0.2144 0.3434 -0.2487 -0.1786 0.0770
-0.0364 0.2573 0.2733 0.2734 -0.2082
-0.4904 0.1167 -0.4683 -0.1673 -0.2173
-0.0502 0.2612 0.2065 0.0560 -0.2161
0.4515 0.2890 -0.3668 -0.1572 -0.5496
0.2442 0.3133 0.0074 -0.1660 0.4973
0.3413 0.1708 0.0719 -0.2486 0.0906
B. Source Assignment Analysis Using First Two PC’s: values are probabilities
that the artifact sample belongs to the fingerprint source.
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
HS028
HS029
HS034
HS036
01A
16.3
0.9
0.5
0.5
3.7
3.7
2.0
2.6
0.3
0.9
55.2
2.5
0.2
4.4
0.3
05B
51.0
4.3
2.2
2.7
19.7
10.6
4.8
4.0
2.3
4.1
26.6
18.1
2.5
10.3
2.6
08A
4.8
0.5
0.3
0.4
1.7
1.2
0.6
0.6
0.3
0.5
8.2
1.5
0.3
1.2
0.3
11A
2.6
0.8
0.6
0.5
1.8
2.7
1.7
1.6
0.2
0.9
2.9
0.6
0.1
3.1
0.2
23A
0.5
0.3
0.0
0.1
91.4
0.9
0.0
0.0
0.0
0.2
0.0
1.3
0.0
0.3
0.1
28C
1.8
0.4
0.0
0.8
1.3
0.0
0.0
0.0
1.1
0.2
0.7
46.1
0.3
0.0
0.8
62A
1.5
0.0
0.0
0.0
0.0
5.6
0.5
60.5
0.0
0.0
0.1
0.0
0.0
55.6
0.0
124
ANID
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
HS118
HS119
HS120
01A
11.1
29.9
6.2
4.1
0.5
0.6
1.9
0.6
4.0
2.2
1.6
17.7
0.4
11.0
77.5
2.1
0.4
2.5
0.3
2.3
3.2
1.1
1.1
0.9
0.4
05B
39.4
81.0
24.5
14.4
2.3
2.3
10.3
2.9
17.3
8.1
3.3
62.4
3.7
45.8
81.2
8.9
2.7
17.9
2.8
15.9
16.9
3.4
9.4
4.1
2.1
08A
3.2
6.8
2.2
1.5
0.3
0.3
1.1
0.4
1.7
0.9
0.5
4.8
0.4
3.8
22.7
1.0
0.3
1.5
0.3
1.4
1.6
0.5
0.9
0.5
0.3
11A
4.6
7.0
3.2
2.7
0.6
0.7
1.3
0.7
2.4
1.8
1.3
4.8
0.2
2.2
24.5
1.6
0.4
0.6
0.1
0.9
1.7
1.1
0.4
0.9
0.4
23A
7.7
0.8
21.8
6.4
0.0
0.0
27.5
0.0
30.2
1.7
0.0
2.6
0.1
1.3
0.0
4.3
0.1
2.0
0.0
29.0
83.7
0.0
4.4
0.2
0.0
28C
0.1
0.0
0.1
0.0
0.1
0.0
1.4
0.1
0.2
0.1
0.0
0.1
0.4
3.0
0.0
0.1
1.3
62.3
0.3
53.8
1.0
0.0
43.5
0.2
0.6
62A
19.6
0.5
4.8
1.6
0.0
0.0
0.0
0.0
0.3
0.0
0.9
5.7
0.0
0.7
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
C. Source Assignment Analysis Using First Three PC’s:
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
HS028
HS029
01A
7.3
0.9
0.8
1.6
2.1
1.2
0.7
3.3
1.8
0.7
68.7
3.0
1.8
05B
49.2
1.6
1.5
12.4
4.3
1.4
0.8
6.7
2.2
1.0
4.2
22.3
1.4
08A
12.3
3.2
2.1
1.7
7.3
5.9
3.5
3.3
0.9
3.2
9.5
4.9
0.7
11A
5.6
3.4
2.6
1.1
6.1
3.9
1.4
2.9
0.1
3.2
2.2
1.0
0.1
23A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.0
0.0
28C
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
2.4
0.0
0.0
62A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
14.2
0.0
0.0
0.1
0.0
0.0
125
ANID
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
HS118
HS119
HS120
01A
1.2
2.0
2.9
4.5
6.5
11.2
1.9
0.9
8.3
0.8
11.5
3.1
0.8
3.3
2.4
2.9
67.3
2.8
1.7
7.5
1.9
3.2
2.0
2.4
1.8
1.1
1.3
05B
1.3
1.5
4.2
6.7
47.0
8.1
12.0
1.8
1.9
1.6
6.7
12.5
0.8
4.9
0.9
5.4
12.0
10.6
13.0
6.1
1.1
27.8
4.2
9.3
10.6
2.4
8.8
08A
5.8
0.8
12.1
20.5
7.2
4.1
1.6
2.2
2.1
2.5
4.1
4.2
2.8
16.1
0.8
12.9
31.5
4.4
1.6
3.0
0.7
4.6
6.7
2.6
3.4
3.0
1.5
11A
2.9
0.1
11.5
16.4
8.9
5.4
1.6
2.8
0.8
2.9
3.6
6.1
0.9
13.2
0.0
6.8
45.8
5.6
0.8
0.4
0.0
1.6
6.1
4.5
0.8
3.5
1.0
23A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
1.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
28C
0.0
0.0
0.1
0.1
0.4
0.2
0.1
0.0
3.5
0.0
0.8
0.2
0.0
0.1
0.0
0.0
0.0
0.1
0.0
0.1
0.0
0.0
0.0
0.1
0.0
0.0
0.0
62A
0.0
0.0
0.0
0.0
0.3
3.9
0.0
0.0
0.0
0.0
1.1
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
28C
0.3
0.0
0.0
0.1
0.0
0.0
0.0
0.0
0.0
0.0
0.3
62A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
D. Source Assignment Analysis Using First Four PC’s:
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
01A
2.0
0.4
0.5
0.5
0.7
0.4
0.3
6.4
0.6
0.2
34.3
05B
76.6
4.4
2.9
2.8
7.6
3.6
2.2
4.0
1.1
4.6
2.9
08A
23.2
5.9
8.7
8.7
10.0
5.0
3.8
9.5
5.7
3.2
25.5
11A
0.4
0.1
0.1
0.0
0.2
0.3
0.2
1.3
0.0
0.1
0.5
23A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.3
0.0
0.0
126
ANID
HS028
HS029
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
HS118
HS119
HS120
01A
0.4
0.6
0.4
0.7
0.9
1.5
4.8
9.5
0.5
0.5
8.8
0.4
3.9
1.0
0.4
0.8
0.8
0.5
7.6
1.0
0.5
1.6
0.6
0.7
0.6
1.6
0.3
0.4
0.5
05B
3.5
0.9
3.4
0.9
5.9
5.7
19.7
3.2
2.0
3.7
1.5
4.0
2.2
9.8
2.3
9.0
0.8
26.3
2.3
28.3
2.2
2.1
0.8
4.8
13.4
30.1
2.6
8.3
4.1
08A
5.9
5.2
5.0
5.5
11.9
16.5
20.1
10.4
8.3
8.9
6.1
7.1
14.0
14.8
4.6
9.0
5.2
5.5
40.2
15.4
8.3
13.4
5.1
10.7
8.4
11.1
4.0
7.5
8.4
11A
0.1
0.0
0.3
0.0
0.5
1.0
0.6
0.4
0.1
0.1
0.1
0.1
0.2
0.2
0.3
0.5
0.0
0.2
2.3
0.2
0.0
0.1
0.0
0.1
0.2
0.2
0.0
0.1
0.0
23A
0.0
0.0
0.0
0.1
0.0
0.0
0.0
0.0
0.0
0.0
2.9
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
28C
0.0
0.0
0.0
0.0
0.1
0.1
1.2
0.0
0.0
0.0
0.2
0.0
0.0
0.2
0.0
0.0
0.1
0.1
0.0
0.6
0.1
0.0
0.0
0.0
0.1
0.5
0.0
0.0
0.0
62A
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
127
E. Summary of Source Assignment Analyses For Low Chromium Samples:
Best Fitting Source
(minimum 5% fit)
ANID
HS003
HS009
HS015
HS017
HS026
HS027
HS028
HS029
HS034
HS039
HS042
HS063
HS079
HS089
HS097
HS098
HS102
HS105
HS118
PC 1-2
05B
23A
UNK
62A
UNK
01A
28C
UNK
62A
05B
05B
05B
05B
05B
05B
05B
28C
23A
28C
PC 1-3
05B
08A
UNK
62A
UNK
01A
05B
UNK
08A
08A
08A
05B
05B
08A
01A
05B
01A
08A
05B
PC 1-4
05B
08A
UNK
08A
UNK
01A
08A
08A
UNK
08A
08A
08A
08A
05B
08A
05B
08A
05B
UNK
Counts of assignments at
1% probability or better
01A 05B 08A 11A 23A 28C
3
3
3
2
0
1
2
3
2
2
1
1
1
2
2
2
0
0
3
3
2
3
0
0
3
2
1
0
0
0
3
3
3
2
0
0
2
3
3
0
1
1
1
2
1
0
0
0
2
3
3
2
0
0
1
3
3
2
1
0
3
3
3
2
0
0
3
3
3
2
1
1
2
2
2
2
1
0
2
2
3
2
1
1
3
3
3
3
0
0
3
3
3
2
1
0
3
3
3
0
1
1
2
3
3
2
1
0
2
3
2
0
1
1
IV. Artifact Source Assignments
ANID
HS003
HS004
HS005
HS007
HS009
HS014
HS015
HS017
HS021
HS026
HS027
HS028
PRIMARY SOURCE POSSIBLE SOURCE
ASSIGNMENT
ASSIGNMENT
62B
5B
UNKNOWN
UNKNOWN
13C
14A
13C
14A
UNKNOWN
5B
UNKNOWN
61A
UNKNOWN
UNKNOWN
62A
28A
UNKNOWN
UNKNOWN
1A
5B
UNKNOWN
UNKNOWN
TRACE OF
13C
23A
5A
5B
5B
62A
1
0
0
2
0
0
0
0
1
1
0
1
0
0
0
0
0
0
0
128
ANID
HS029
HS034
HS036
HS039
HS042
HS063
HS064
HS065
HS068
HS069
HS070
HS072
HS079
HS084
HS085
HS088
HS089
HS097
HS098
HS099
HS102
HS103
HS104
HS105
HS107
HS118
HS119
HS120
PRIMARY SOURCE POSSIBLE SOURCE
ASSIGNMENT
ASSIGNMENT
TRACE OF
UNKNOWN
UNKNOWN
5B
UNKNOWN
UNKNOWN
62A
28A
62B
5B
5B
62B
5B
2A
2A
2B
13C
14A
13C
UNKNOWN
2A
13C
2A
UNKNOWN
UNKNOWN
5B
UNKNOWN
UNKNOWN
61A
62B
5B
UNKNOWN
28A
65A
5B
62B
5B
1A
UNKNOWN
UNKNOWN
5B
14A
13C
UNKNOWN
UNKNOWN
28C
UNKNOWN
UNKNOWN
UNKNOWN
13C
2A
UNKNOWN
23A
2B
UNKNOWN
28C
13C
13C
14A
129
REFERENCES CITED
Adams, Jenny L.
1993 Toward Understanding the Technological Development of Manos and Metates.
KIVA 58(3):331-344.
Binford, Lewis R.
1980 Willow Smoke and Dogs' Tails: Hunter-Gatherer Settlement Systems and
Archaeological Site Formation. American Antiquity 45(1):4-20.
Biskowski, Martin
1997 The Adaptive Origins of Prehispanic Markets in Central Mexico: The Role of
Maize-Grinding Tools and Related Staple Products in Early State Economies. Ph.
D. dissertation, Anthropology, University of California Los Angeles.
2000 Maize Preparation and the Aztec Subsistence Economy. Ancient Mesoamerica
11:293-306.
2004 Specialization and Food Preparation at Teotihuacan. Paper presented at the 69th
Annual Meeting of the Society for American Archaeology in the symposium
"Craft Production at Terminal Formative and Classic Period Teotihuacan",
Montreal.
2008 Maize-Grinding Tools in Prehispanic Central Mexico. In New Approaches to
Old Stones: Recent Studies of Ground Stone Artifacts, pp. 144-155.
Biskowski, Martin, Michael D. Glascock and Hector Neff
1999 Grinding Tools, Source Analyses, and Exchange. Paper presented at the 64th
Annual Meeting of the Society for American Archaeology in the symposium,
"Postclassic Systems of Production, Distribution, and Consumption in Central and
Western Mexico: Contributions from Materials Composition Analyses", Chicago.
Biskowski, Martin and Karen D. Watson
2007 The Changing Patterns of Maize Preparation in Central Mexico. Paper presented
at the 72nd Annual Meeting of the Society for American Archaeology in the
symposium, "Inter-Valley Relations in the Central Mexican Highlands:
Developing Comparative and Diachronic Perspectives", Austin, Texas.
2008 Changing Approaches to Maize Preparation at Portezuelo. Paper presented at
the 73 Annual Meeting of the Society for American Archaeology, Vancouver,
British Columbia.
130
Blucher, Darlena K.
1971 Late Preclassic Cultures in the Valley of Mexico. Ph. D. dissertation,
Department of Anthropology, Brandeis University, University Microfilms
International, Ann Arbor, Michigan.
Borejsza, Aleksander
2006 Agricultural Slope Management and Soil Erosion in Tlaxcala, Mexico.
Unpublished doctoral dissertation, Department of Archaeology, University of
California.
Borejsza, Aleksander, Isabel Rodríguez López and Charles Frederick
2008 Agricultural Slope Management and Soil Erosion at La Laguna, Tlaxcala,
Mexico. Journal of Archaeological Science 35:1854-1866.
Bostwick, Todd W. and James H. Burton
1993 A Study in Sourcing Hohokam Basalt Ground Stone Implements. KIVA
58(3):357-372.
Cabrera Castro, Ruben, Saburo Sugiyama and George L. Cowgill
1991 The Templo De Quetzalcoatl: A Preliminary Report. Ancient Mesoamerica
2:77-92.
Carballo, David M.
2005 Proto-Urban Social Transformations and Community Organization at La
Laguna, Tlaxcala, During the Late Pre-Classic. FAMSI.
2006 Proto-Urban Social Transformations and Community Organization at La
Laguna, Tlaxcala, During the Late Pre-Classic. Internet report available at
http://www.famsi.org/reports/05018/index.html.
Carballo, David M., Jennifer Carballo and Hector Neff
2007 Formative and Classic Period Obsidian Procurement in Central Mexico: A
Compositional Study Using Laser Ablation-Inductively Coupled Plasma-Mass
Spectrometry. Latin American Antiquity 18(1):27-43.
Carballo, David M. and Thomas Pluckhahn
2007 Transportation Corridors and Political Evolution in Highland Mesoamerica:
Settlement Analyses Incorporating Gis for Northern Tlaxcala, Mexico. Journal of
Anthropological Archaeology 26:607-629.
Castañeda Saldaña, Hilda
1976 Utensilios De Molienda De Teotihuacan, E.N.A.H., Mexico, D.F.
131
Clark, John E.
1988 The Lithic Artifacts of La Libertad, Chiapas, Mexico: An Economic
Perspective. In Papers of the New World Archaeological Foundation, pp. 1-286.
vol. Number 52, Susanna M. Ekholm, general editor. New World Archaeological
Foundation, Brigham Young University, Provo, Utah.
Cook, Scott
1982 Zapotec Stoneworkers: The Dynamics of Rural Simple Commodity Production
in Modern Mexican Capitalism. University Press of America, Washington DC.
de Landero, P.
1922 Canteros Del Valle. In La Poblacion Del Valle De Teotihuacan, Tomo Ii, edited
by Manuel Gamio, pp. 67-79. Instituto Nacional Indigenista, Mexico.
Delu, Antonina M.
2007 The Ground Stone Tools of Caye Coco, Belize. Occasional Publication Number
12. Institute for Mesoamerican Studies. University at Albany, State University of
New York. Albany, New York.
Diehl, Richard A.
1983 Tula: The Toltec Capital of Ancient Mexico. Thames and Hudson Ltd., New
York.
Fournier, Patricia
2001 The Otomí. In The Oxford Encyclopedia of Mesoamerican Cultures. Oxford
University Press, New York.
Fournier, Patricia and Victor H. Bolaños
2000 Cosmovisión Y Religiosidad Otomianas: Prácticas Funerarias En La Región De
Tula, México (650-950 D.C.). Paper presented at the VIII Congreso
Latinoamericano sobre Religión e Identidad, Padua, Italy.
2007 The Epiclassic in the Tula Region Beyond Tula Chico. In Twin Tollans:
Chichén Itzá, Tula, and the Epiclassic to Early Postclassic Mesoamerican World,
edited by Jeff Karl Kowalski and Cynthia Kristan-Graham, pp. 481-530.
Dumbarton Oaks Research Library and Collections, Harvard University Press,
Washington D.C.
Fournier, Patricia and Laura E. Chavez
2000 Tula: Early Postclassic Sacred and Secular Architecture in Central Mexico.
Paper presented at the Chaco Architecture Conference, New Mexico.
132
Fournier, Patricia and Alejandro Pastrana
1999 La Obsidiana De Sinana. Ponencia presentada en el Coloquio Estatal de
Otopames.
Fratt, Lee and Maggie Biancaniello
1993 Homol'ovi Iii Ground Stone in the Raw: A Study of the Local Sandstone Used
to Make Ground Stone Artifacts. KIVA 58(3):373-391.
García Cook, Ángel
1967 Analisis Tipologico De Artefactos. Serie Investigaciones, 12. INAH, Mexico
City.
1981 The Historical Importance of Tlaxcala in the Cultural Development of the
Central Highlands. In Supplement to the Handbook of Middle American Indians,
Archaeology, edited by Jeremy A. Sabloff, pp. 244-276. vol. 1. University of
Texas Press, Austin.
Glascock, Michael D.
1992 Characterization of Archaeologcial Ceramics at Murr by Neutron Activation
Analysis and Multivariate Statistics. In Chemical Characterization of Ceramic
Pastes in Archaeology, edited by Hector Neff, pp. 11-26. Prehistory Press,
Madison, Wisconsin.
Gueyger, Andrea and Martin Biskowski
2005 Maize-Grinding Technology in Formative Tlaxcala. Paper presented at the 70th
Annual Meeting of the Society for American Archaeology, in the symposium
"Formative Social Transformations in Central and Western Mexico", Salt Lake
City, Utah.
Hayden, Brian (editor)
1987a Lithic Studies among the Contemporary Highland Maya. The University of
Arizona Press, Tucson, AZ.
1987b Past to Present Uses of Stone Tools and Their Effects on Assemblage
Characteristics in the Maya Highlands. In Lithic Studies among the Contemporary
Highland Maya, edited by Brian Hayden, pp. 160-234. The University of Arizona
Press, Tucson, AZ.
1987c Traditional Metate Manufacturing in Guatemala Using Chipped Stone Tools.
In Lithic Studies among the Contemporary Highland Maya, edited by Brian
Hayden, pp. 8-119. The University of Arizona Press, Tucson, AZ.
133
Hayden, Brian and Aubrey Cannon
1984 The Structure of Material Systems: Ethnoarchaeology in the Maya Highlands.
Society for American Archaeology, Washington DC.
Healan, Dan M.
1977 Architectural Implications of Daily Life in Ancient Tollan, Hidalgo, Mexico.
World Archaeology 9(2):140-156.
1989 Tula of the Toltecs:Excavations and Survey. University of Iowa Press, Iowa
City.
1993 Local Versus Non-Local Obsidian Exchange at Tula and Its Implications for
Post-Formative Mesoamerica. World Archaeology 24(3):449-466.
Horsfall, Gayel
1987 A Design Theory Perspective on Variability in Grinding Stones. In Lithic
Studies among the Contemporary Highland Maya, edited by Brian Hayden, pp.
332-377. University of Arizona Press, Tucson, Arizona.
Lesure, Richard G.
2007 Quinto Informe Técnico Parcial Del Proyecto "Investigaciones Del Formativo
En La Región De Apizaco, Tlaxcala". Archivo Técnico, INAH.
Lesure, Richard G., Aleksander Borejsza, Jennifer Carballo, Charles Frederick, Virginia
Popper and Thomas A. Wake
2006 Chronology, Subsistence, and the Earliest Formative of Central Tlaxcala,
Mexico. Latin American Antiquity 17(4):474-492.
Linné, Sigvald
2003 Mexican Highland Cultures: Archaeological Researches at Teotihuacan,
Calpulalpan, and Chalchicomula in 1934-1935. Reprinted. University of
Alabama Press, Tuscaloosa and London. Originally published 1942, The
Ethnographical Museum of Sweden, Stockholm.
MacNeish, Richard S.
1971 Ancient Mesoamerican Civilization. In Prehistoric Agriculture, edited by Stuart
Struever, pp. 143-156. The Natural History Press, Garden City, New York.
1992 Origins of Agriculture and Settled Life. University of Oklahoma Press, Norman.
Mandeville, Margaret D. and Dan M. Healan
1989 Architectural Remains in the El Corral Locality. In Tula of the Toltecs, edited
by Dan M. Healan, pp. 171-202. University of Iowa Press, Iowa City.
134
Mauldin, Raymond P.
1991 Agricultural Intensification in the Mogollon Highlands. In Mogollon V, edited
by P. Beckett, pp. 62-74. COAS Publishing and Research, Las Cruces, New
Mexico.
1993 The Relationship between Ground Stone and Agricultural Intensification in
Western New Mexico. KIVA 58(3):317-330.
Niederberger, Christine
1976 Zohapilco: Cinco Milenios De Ocupacion Humana En Un Sitio Lacustre De La
Cuenca De Mexico. Instituto Nacional de Antropologia e Historia, Mexico.
1979 Early Sedentary Economy in the Basin of Mexico. Science 203(4376):131-142.
Read, Dwight W.
1985 The Substance of Archaeological Analysis and the Mold of Statistical
Method:Enlightenment out of Discordance? In For Concordance in
Archaeological Analysis: Bridging Data Structure, Quantitative Technique and
Theory, edited by Christopher Carr, pp. 45-86. Westport Publishers, Kansas City.
Rodríguez, Alfonso Torres, Juan Cervantes and Patricia Fournier
2000 Las Relaciones Entre El Centro Y La Periferia: El Caso De Las Comunidades
Del Clásico En La Región De Tula, México. Boletín de Antropología Americana.
Instituto Panamericano de Geografía e Historia. Mexico.
Sanders, William T., Jeffrey R. Parsons and Robert S. Santley
1979 The Basin of Mexico: Ecological Processes in the Evolution of a Civilization.
Academic Press, New York.
Sanders, William T., Michael West, Charles Fletcher and Joseph Marino
1975 The Formative Period Occupation of the Valley. The Teotihuacan Valley
Project Final Report, Vol. 2. Occasional Papers in Anthropology, No. 10.
Department of Anthropology, Pennsylvania State University, University Park,
Pennsylvania.
Schneider, Joan S. and Philip C. LaPorta
2008 Geological Constraints on Ground Stone Production and Consumption in the
Southern Levant. In New Approaches to Old Stones: Recent Studies of Ground
Stone Artifacts, edited by Yorke M. Rowan and Jennie R. Ebeling, pp. 19-40.
Approaches to Anthropological Archaeology, Thomas E. Levy, general editor.
Equinox Publishing Ltd., London.
135
Searcy, Michael T.
2005 Mayan Metate Ethnoarchaeology. M. A. Thesis, Department of Anthropology,
Brigham Young University.
Snow, Dean R.
1969 Ceramic Sequence and Settlement Location in Pre-Hispanic Tlaxcala. American
Antiquity 34(2):131-145.
Sotomayor Castañeda, Alfredo
1968 Estudio Petrográfico Del Area De San Juan Teotihuacan, Edo. De Mexico. In
Materiales Para La Arqueologia De Teotihuacan, 17, edited by J. L. Lorenzo, pp.
41-49. Instituto Nacional de Antropologia e Historia, Mexico, D.F.
Spence, Michael W., Christine D. White, Patricia Fournier, Emily Webb and Fred J.
Longstaffe
2011 The Chapantongo Site: Oxygen Isotope Analysis and Epiclassic Population
Mobility in the Valley of Mezquital. Paper presented at the 76th Annual Meeting
of the Society for American Archaeology, Sacramento, California.
Spink, Mary Louise
1984 Metates as Socioeconomic Indicators During the Classic Period at Copan,
Honduras. Ph.D. Dissertation, Department of Anthropology, Pennsylvania State
University.
Stroh, Jr., Edward G.
1975 The Ground Stone of Tula, Hidalgo, Mexico: Description and Distributional
Analysis. Unpublished M. A. Thesis, Department of Anthropology, University of
Missouri.
Sugiyama, Saburo
1993 Worldview Materialized in Teotihuacan, Mexico. Latin American Antiquity
4(2):103-129.
Tolstoy, Paul
1971 Utilitarian Artifacts of Central Mexico. In Handbook of Middle American
Indians, edited by Robert Wauchope, Gordon F. Ekholm and Bernal Ignacio, pp.
270-296. vol. 10. University of Texas Press, Austin.
1975 Settlement and Population Trends in the Basin of Mexico (Ixtapaluca and
Zacatenco Phases). Journal of Field Archaeology 2(4):331-349.
1989 Coapexco and Tlatilco: Sites with Olmec Materials in the Basin of Mexico. In
Regional Perspectives on the Olmec, edited by Robert J. Sharer and David C.
136
Grove, pp. 85-121. School of American Research Advanced Seminar Series,
Jonathan Haas, general editor. Cambridge University Press, Cambridge.
Tolstoy, Paul and Suzanne K. Fish
1975 Surface and Subsurface Evidence for Community Size at Coapexco, Mexico.
Journal of Field Archaeology 2(1/2):97-104.
Tolstoy, Paul, Suzanne K. Fish, Martin W. Boksenbaum, Kathryn Blair Vaughn and C.
Earle Smith
1977 Early Sedentary Communities of the Basin of Mexico. Journal of Field
Archaeology 4(1):91-106.
Vaillant, George C.
1930 Excavations at Zacatenco. Anthropological Papers of The American Museum of
Natural History XXXII, Part I:1-197.
1931 Excavations at Ticoman. Anthropological Papers of The American Museum of
Natural History XXXII, Part II:199-439.
1935 Excavations at El Arbolillo. Anthropological Papers of The American Museum
of Natural History XXXV, Part II:137-279.
Vaillant, Suzannah B. and George C. Vaillant
1934 Excavations at Gualupita. Anthropological Papers of The American Museum of
Natural History XXXV, Part 1:1-135.
Watson, Karen D.
2007 Operational Chains for Maize Grinding Tools in Mesoamerica. Unpublished
ms., California State Univeristy, Sacramento.
Watson, Karen D., Martin Biskowski and Michael D. Glascock
2006 Patterns of Grinding Tool Exchange in Central Mexico. Paper presented at the
71st Annual Meeting of the Society for American Archaeology, San Juan, Puerto
Rico.