ΜΕΛΕΤΗ ΠΡΟΕΛΕΥΣΗΣ ΚΑΙ ΤΕΧΝΟΛΟΓΙΑΣ
ΑΡΧΑΙΑΣ ΚΕΡΑΜΙΚΗΣ:
ΔΥΝΑΤΟΤΗΤΕΣ ΚΑΙ ΠΕΡΙΟΡΙΣΜΟΙ
Βασίλης Κυλίκογλου
Εργαστήριο Αρχαιολογικών Υλικών
Ινστιτούτο Νανοεπιστήμης και Νανοτεχνολογίας
Ε.Κ.Ε.Φ.Ε. Δημόκριτος
Provenance Postulate
“…that there exist differences in chemical [and mineralogical]
composition between different natural sources that exceed in
some recognizable way, the differences observed within a given
source.” (Weigand, P.C., G. Harbottle, and E.V. Sayre 1977:24 )
In most cases it has been accepted a priori - Chemistry
In many cases it has been investigated and challenged
This is where chemistry meets petrology and mineralogy
Provenance meets Technology
TYPES OF POTTERY ANALYSIS PROJECTS
Production and distribution of a particular ware or shape
Assumption: The chemical composition of the paste
is characteristic for a ceramic ware type from a
certain production place, due to used raw materials
and paste recipe.
e.g. Mycenaean decorated pottery
e.g. Archaic terracotta figurines
Correlation of groups with reference material
Study of whole pottery assemblages (Usually no assumptions)
1st level:
Physicochemical variability of ceramic pastes
Variability of raw materials within a site or an area
Raw materials for particular wares (cooking vs tableware)
Technological variability
2nd level:
Correlation of groups with raw materials
Correlation of groups with reference material
Correlation of groups with similar from other sites
CHEMICAL CHRACTERISATION OF CERAMICS FOR
PROVENANCE
Methodology: Formation of reference (control) groups
a. Pure archaeological information - Published Data
b. Largest group = Local
d. Clays
c. Kiln pottery and wasters
Technique requirements
High number of trace elements
High accuracy and precision
Pereruela : problem with
known solution
Pottery making community
1
:
1
Pottery
Pottery is made in the same way by all potters with local clays
Same technology of manufacture
Same chronology
Ideal case to test the validity of “reference” groups
Geological map of Pereruela
PC1 vs PC2 of pots, clays and paste
2
***
**
0
-3
-2
-1
0
PC 1
1
*
-2
Redondo
Pastor
-4
Ramos
Riesgo
Riesgo's paste
Red clays
Kaolin
PC 2
-6
2
3x11 pots from Redondo
010B
015B
020B
025B
110B
115B
120B
125B
210B
215B
220B
225B
310B
315B
320B
325B
410B
415B
420B
425B
510B
515B
520B
525B
610B
615B
620B
625B
710B
715B
720B
725B
810B
815B
820B
825B
910B
915B
920B
925B
Elemental concentrations in ppm
Sacrificing a casserole
160
120
80
La
40
Th
0
Sc
Hf
Multisampling from casserole RED001
Monazite crystals
Monazite (Ce, La, Pr, Nd, Th, Y)PO4
monazite
Zircon ZrSiO4, Hf
250 m
NEOGENE CLAY VARIABILITY IN CENTRAL AND
EAST CRETE
MM / M
MM / L
MM / M
MM / L
2 MA
NEOGENE
MM / Br
PLIOCENE
MIOCENE
20 MA
OLIGOCENE
PALEOGENE
EOCENE
PALEOCENE
Agios Syllas sampling points
Discriminant Analysis plot of Neogene deposits
with multiple samples
All Central and Eastern Cretan deposits
Indicators
Ambelouzos Cr/Th low
Pliocene high Ca low Th/U
Late Miocene low Co, Fe, Ni
Kiln pottery (and wasters) in formation of reference groups
Kommos kiln
KOM1
KOM2
KOM17
KOM20
KOM3
KOM9
KOM11
KOM8
KOM57
KOM5
KOM35
KOM12
KOM53
KOM38
KOM42
KOM23
KOM30
KOM4
KOM33
KOM43
KOM7
KOM28
KOM47
KOM51
KOM48
KOM45
KOM14
KOM15
KOM22
KOM31
KOM19
KOM36
KOM34
KOM29
KOM32
KOM25
KOM39
KOM41
KOM52
KOM6
KOM13
KOM24
KOM46
KOM49
KOM50
KOM27
KOM37
KOM40
KOM44
KOM55
KOM56
KOM54
KOM16
KOM26
KOM21
KOM10
KOM18
Dendrogram with all the elements analysed
0.182
0.164
0.146
0.127
0.109
0.090
0.072
0.054
Na
0.035
Cs
0.017
_______________________________________________________ _______ ____ ____ __
A
B
C
D E
-0.50
KOM26
KOM16
-1.00
KOM21
KOM22
KOM47
KOM51
KOM53
Ln (Cs/La)
KOM12 KOM7
KOM30
KOM15 KOM46
KOM38 KOM48
KOM43
KOM49
KOM14
KOM13 KOM42
KOM41 KOM23
KOM24
*
Ln(Cs/La)
-1.50
****
KOM39
*****
KOM19
**
KOM45
KOM2
KOM36
******
***
KOM3
KOM37
KOM50
KOM32
KOM34 KOM27
KOM20
-2.00
KOM40
Fine
Medium
+sec calc
Medium
KOM17
KOM18
KOM10
-2.50
*
KOM33, KOM35
**
KOM5, KOM11
***
KOM8, KOM9
**** KOM28, KOM52
***** KOM4, KOM31
****** KOM25, KOM29, KOM57
Group 1
Group 2
Group 3
Categories of association of crystalline phases by XRD
No I-M (Vc-Vc+)
D and I-M (Vc)
No Cl No D
Cl
No I-M (TV)
D and I-M (IV-Vc+)
No Cl No D
Cl
No I-M (Vc-Vc+)
D and I-M (IV-Vc)
No Cl No D (NV)
Cl (NV)
-3.00
6.40
KOM49
KOM37
KOM50
KOM46
KOM24
KOM27
Ln (Na/La)
6.00
KOM51
KOM43
**** KOM48
KOM28 KOM47
KOM22
5.60
KOM21
KOM26
KOM16
*****
KOM15
KOM31
KOM40
*
KOM41
KOM39
******
KOM38
KOM29
KOM13
KOM32
KOM14 KOM53
KOM19
KOM34
**
Medium
+sec calc
KOM5
KOM17
5.20
KOM57
KOM8
KOM10
Fine
*
KOM33, KOM42
**
KOM9, KOM12, KOM36
***
KOM11, KOM20
**** KOM2, KOM52
***** KOM25, KOM45
****** KOM3, KOM4, KOM30
Medium
***
KOM35
KOM18
Group 1
Group 2
Group 3
Categories of association of crystalline phases by XRD
No I-M (Vc-Vc+)
D and I-M (Vc)
No Cl No D
Cl
No I-M (TV)
D and I-M (IV-Vc+)
No Cl No D
Cl
No I-M (Vc-Vc+)
D and I-M (IV-Vc)
No Cl No D (NV)
4.80
Cl (NV)
Ln(Na/La)
KOM7
KOM23
Analcime presence
D
Sp*
D
Q
6.30
KOM49
KOM37
P
6.20
D
Sp*
P
KOM50
KOM46
Ln(Na/La)
6.10
D
An
6.00
An D
P
An
P
An D D
P
D
P
D
Q
P
Q
P
KOM27
P
Q
P
P
Q
D D
An
5.90
KOM43
P D
D
Sp*
Q
An P
5.80
150
5
10
200
250
Analcime (CPS)
KOM49
15
20
(Cu Kα)
25
ο
2θ
30
35
40
45
300
350
Summary
High-fired individuals with high Na content
Medium-fired individuals with low alkali content
Low-fired fine-grained individuals with high Cs content
KOM1
KOM2
KOM17
KOM20
KOM3
KOM9
KOM11
KOM8
KOM57
KOM5
KOM35
KOM12
KOM53
KOM38
KOM42
KOM23
KOM30
KOM4
KOM33
KOM43
KOM7
KOM28
KOM47
KOM51
KOM48
KOM45
KOM14
KOM15
KOM22
KOM31
KOM19
KOM36
KOM34
KOM29
KOM32
KOM25
KOM39
KOM41
KOM52
KOM6
KOM13
KOM24
KOM46
KOM49
KOM50
KOM27
KOM37
KOM40
KOM44
KOM55
KOM56
KOM54
KOM16
KOM26
KOM21
KOM10
KOM18
KOM1
KOM3
KOM22
KOM10
KOM12
KOM2
KOM53
KOM36
KOM42
KOM45
KOM38
KOM5
KOM49
KOM11
KOM18
KOM23
KOM31
KOM19
KOM29
KOM47
KOM30
KOM20
KOM24
KOM34
KOM52
KOM37
KOM4
KOM7
KOM27
KOM39
KOM26
KOM43
KOM33
KOM50
KOM51
KOM17
KOM9
KOM41
KOM40
KOM28
KOM15
KOM14
KOM16
KOM13
KOM48
KOM35
KOM6
KOM32
KOM25
KOM46
KOM57
KOM8
KOM44
KOM55
KOM56
KOM54
KOM21
0.182
0.164
0.146
0.127
0.109
0.090
0.072
0.054
0.034
0.030
0.035
0.027
0.023
0.020
0.017
0.016
0.013
0.010
0.006
0.003
______________________________________________________________________
_______________________________________________________ _______ ____ ____ __
A
B
C
D E
1 to 4
____
5-6
Why trace elements?
Occurrence and role of trace elements
•Distribution of trace elements is controlled by solubility
and speciation
•Cation Exchange Capacity
•Specific to localized environments
In General
Trace elements may characterize the specific
geological environment
provenance
Major elements characterize the type of the
geological environment and the treatment of the
materials
technology
Elements determined routinely in non-metallic archeological materials
WD-XRF
NAA
ICP-MS
Mycenaean
pottery
distribution
Functions requiring advanced
mechanical performance
Transportation
Storing
Functions requiring advanced
thermal performance
Cooking
metallurgy and
glassmaking
Tableware
STUDY OF CERAMIC TECHNOLOGY
“Traditional” field in Archaeology / Anthropology
History of technology
Explain human behaviour
Η διάδοση της τεχνολογίας της κεραμικής ομάδας
Καστρί στο Αιγαίο, κατά την Πρώιμη Εποχή του
Χαλκού ΙΙ
Early Bronze Age Phases at Akrotiri
• Late Neolithic
• ECI early
• ECI late
• ECII early (“Keros Syros”)
• ECII late – Kastri Group phase
Palamari, Skyros
Kastri, Syros
Poliochni
Palamari
Poliochni
Kastri
Kastri, Syros
Troia
Kastri Group Vessels from Akrotiri,
Entrance, Chamber
2 Pillar Pit 35
Theran Local Fabric in plain and slipped wares
? Theran DOL
Melian DOL
Talc Ware
Talc Schist Fabrics – Siphnos?
Naxian Granitic Fabrics
Amorgian Fabrics
Kean Schist Fabrics
Kastri Group
Tankard in Schist
fabric that occurs in
collared jar transport
vessels
Melian Volcanic Glass Fabrics
Melian Fine Fabrics
Akrotiri 03/151
Knossos
Substantial exchange among S. Aegean
centers
Copying of shapes made using local
recipes (EBI copy recipes)
NO importation from Anatolia
Site of Akrotiri, Thera (Santorini)
Middle Cycladic Period at Akrotiri:
(Knappett & Nikolakopoulou 2008)
(LCIA distruction level ca.1650-1600 BC)
Cooking ware at BA Akrotiri: Syn- and diachronic variation in fabrics
MC early
MC Phase C - LCIA
LOCAL FABRICS
FN to ECII late
Field of view: 7.4mm
IMPORTS MC/ LC
MC Phase B
Naxos – wmb-schist-1
LCIA
Naxos – mica-schist 2
MC Phase C - LCIA
Naxos - granitic
Major change in local cooking ware technology in BA Akrotiri with
onset of MCC: addition of platy phyllite
How does phyllite tempering influence material properties in clay-based
ceramics?
Experimental briquettes
clay
temper
workable
paste
phyllite
briquette
test bars
5 mm
quartz or granite
Performance properties:
Fracture strength
Mechanical
properties
Toughness
(fracture energy)
Related to material
integrity
Thermal shock resistance
Thermal
properties
Thermal conductivity
Related to suitability to
be used in cooking
(e.g., heat distribution)
Performance properties:
► Fracture strength:
(force applied for crack
initiation)
► Toughness:
(= fracture energy:
energy required for initiation
AND propagation of a crack)
► Thermal shock
Describes a material‘s ability to withstand
sustained loads without a crack initiating
Describes a material‘s ability to absorb impact
without loosing structural integrity
Survive sudden drastic temperature changes
resistance:
► Thermal
conductivity:
Measure of heat transfer in a material
Fracture strength
(1) Highly tempered materials generally rel. low strength
(2) Platy tempers better than bulky temper
Bulky temper (granite)
Platy temper (phyllite)
untempered
10 % temper
40% platy
temper
temper
40% bulky temper
550°C
850°C
1050°C
550°C
850°C
1050°C
Fracture strength depends on flaws in a material
different geometries of
damaged zones → less
flaws with platy temper
Toughness
(1) Highly tempered materials generally high toughness
(2) At high firing temperatures bulky temper better than platy temper
Bulky temper (granite)
Platy temper
(phyllite)
40% temper
10 % temper
untempered
550°C
850°C
1050°C 550°C
850°C
1050°C
Reaction to thermal shock
important for high TSR
Critical DT for crack initiation
Ceramic with
brittle fracture
Avoid crack initiation
DTC
Ceramic
with stable
fracture
DTC’
Avoid crack propagation
Thermal shock resistance
Material with higher toughess better able to dissipate energy,
expected to be better able to accommodate thermal stresses
→ Phyllite tempered materials shows higher strength reduction upon thermal
shocking, appears not particulary well suited to absorb thermal stresses
Thermal conductivity
▶ decreases with addition of
phyllite (temper particles
act as heat barriers)
Measurement setup
( due to low thermal conductivity of
sheet silicates parallel to sheets )
Summary:
Influence of phyllite tempering on performance characteristics
beneficial
Strength
detrimental
x
Toughness
- Low - intermediate fired
- High fired
Limited influence
x
Thermal shock resistance
x
- Relative loss in strength
Thermal conductivity
?
x
Introduction of phyllite temper at Akrotiri:
-
Appears not connected to technological development of cooking
ware towards better performance
-
involves additional step and effort in manufacture
schists and phyllites
Akrotiri
Palaeogeology of pre-eruption Thera
→ Why invest more energy for worse qualtity cooking ware?
Change in fabric in MC Phase C coincides with the addition of a novel shape to
the cooking vessel repertoire at Akrotiri, the tripod cooking pot:
- Cretan shape
- Phyllite tempering of
cooking ware is part of
pottery traditions in Crete
- Import of a shape
- Import of a particular
manufacturing practice
- But no apparent import of
actual cooking vessels
from Crete
Implications
During a time where Minoan influence was on the rise, the introduction of
not only a new shape, but also of a novel ceramic recipe for the cooking
vessels, apparently unconnected to the performance of the vessels, could
imply more far reaching transformations at Akrotiri than have sometimes
been assumed and may be linked to the identity and traditions of the
craftspeople making pottery vessels on the island.
Functionality ?