Rock and Mineral
Collection
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Table of Contents
Introduction
Minerals
Mineral Information
Biotite
Calcite
Fluorite
Galena
Graphite
Gypsum
Hematite
Magnetite
Pyrite
Quartz
Igneous Rocks
Igneous Rock Information
Basalt
Granite
Kimberlite
Obsidian
Pumice
Scoria
Metamorphic Rocks
Metamorphic Rock Information
Anthracite Coal
Gneiss
Marble
Phyllite
Schist
Slate
Quartzite
Sedimentary Rocks
Sedimentary Rock Information
Bituminous Coal
Conglomerate
Coquina
Limestone
Sandstone
Shale
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15
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19
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23
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Introduction
Minerals, by definition, are inorganic, naturally occurring
substances with distinct physical properties and crystalline structures.
You probably think of minerals as beautiful gemstones in jewelry or
displayed in museums, but most minerals actually occur in rocks. Rocks
are solids composed of mineral particles. In other words, minerals grow in
nature and are then broken down into small particles through various
weathering processes. Most rocks are composed of combinations of
mineral particles, although there are a few exceptions (some rocks are
composed of plant and animal particles). Rocks can form in three ways.
The way in which a rock forms determines the type of rock. Igneous
rocks are formed when magma or lava cools to a solid state. Metamorphic
rocks are rocks changed from one form to another by intense heat, high
pressure, or very hot fluids. Sedimentary rocks are formed when
fragments of plants, animals, or other rocks are compressed together
and hardened. Sedimentary rocks can also form when mineral crystals
precipitate from water (think of salt that remains when ocean water is
evaporated).
Rocks and minerals play a very important role in our everyday lives.
Not only are they everywhere that we look and in practically everything
that we use or eat, we literally live on them! That’s right, we live on the
outermost portion of the earth, known as the crust, which is composed of
rocks and minerals. Although the ground in general is composed of rock
and soil (soil is made of lots of tiny pieces of rocks and minerals), the
places that you encounter rocks and minerals in your daily life aren’t
limited to the times when you are outside. In fact, minerals are the
natural material from which every inorganic item in our industrialized
society has been manufactured. Often minerals are contained within
rocks, and thus rocks are mined for the materials necessary to produce
many of the things that we use everyday. Anything that contains metal
relies on the mining of rocks to obtain those metals. When you start to
think of all of the appliances and hardware that contain metal, it’s easy to
understand the role that rocks and minerals play in our modern life.
Metals aren’t the only uses for rocks and minerals, however. Often
countertops, floors, and even the walls come directly from rocks. Also,
things such as talcum powder and makeup powder are derived from
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minerals. Talcum powder is made from the mineral talc and many facial
powders add shimmer to your face thanks to mica minerals such as
muscovite. Even soft-serve ice cream from fast food restaurants
contains clay minerals to thicken the texture of the ice cream!
This rock collection contains samples and descriptions of minerals
and all three types of rocks. It is divided into four sections: Minerals,
Igneous Rocks, Sedimentary Rocks, and Metamorphic Rocks. Each section
begins with a general introduction and then includes detailed descriptions
of each sample. Along with descriptions, pictures are included so each
mineral or rock can be correctly identified.
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Minerals
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Mineral Information
Minerals are literally the physical foundation of both our planet and our
industrialized societies. More than 2000 different kinds of minerals have
been identified. There are rock-forming minerals, which consist of the
main minerals observed in rocks. There are industrial minerals, meaning
that they are the main minerals used in manufacturing. There are also
biochemical minerals, which can be manufactured by organisms, but are
still inorganic. For example, the mineral aragonite is used by clams and
mollusks in the construction of their shells. To illustrate the degree to
which minerals are used in our everyday life, consider a pencil. The
rubber eraser is hardened with sulfur; the brass eraser holder is made
from sphalerite and chalcopyrite; mineral powders are used as pigment in
the enamel paint, along with feldspar; the wood is shaped with steel tools
made from hematite or limonite with fluorite flux; and the pencil lead is a
mixture of graphite and kaolinite.
Minerals can be identified by their physical properties, which can be
documented through a series of tests.
• Color is the most obvious property of most minerals, but is not
always conclusive. While a few minerals are always the same color,
the color of most minerals can vary, as the color is generally
caused by “impurities” in the rock.
• The luster of a mineral is the way its surface reflects light. All
minerals have either a metallic luster or a nonmetallic luster.
Minerals with a metallic luster reflect the silver, gold, or copper
sheen reflected by metals; otherwise a mineral’s luster is
nonmetallic.
• Hardness is a measure of resistance to scratching. A harder
object will scratch a softer one. Hard minerals will scratch glass
and cannot be scratched with a knife blade or a masonry nail. Soft
minerals will not scratch glass and can be scratched with a knife
blade or a masonry nail. Mohs Scale of Hardness is widely used by
geologists and engineers to determine relative mineral hardness by
comparing minerals to common household objects or to pieces of
the minerals on Mohs scale.
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Hard
Soft
•
•
Mohs Scale
Of
Hardness
10. Diamond
9. Corundum
8. Topaz
7. Quartz
6. Orthoclase Feldspar
5. Apatite
4. Fluorite
3. Calcite
2. Gypsum
1. Talc
Hardness of Some Common
Objects
6.5 Streak Plate
5.5 Glass, Masonry nail, Knife blade
4.5 Wire (iron) nail
3.5 Copper wire or coin (penny)
2.5 Fingernail
Minerals can also be identified by the way that they break. Some
minerals tend to break into routine shapes, or preferentially break
along a particular plane. These minerals exhibit cleavage. Minerals
that do not exhibit cleavage do not break into a predictable shape
or along a predictable plane.
The streak is the color of a mineral after it has been ground to a
fine powder. To determine a mineral’s streak, the mineral is rubbed
on a streak plate (a tile of unglazed white porcelain) to produce a
line of powder. The color of the powder is the streak, which is a
more reliable indicator of a mineral than the color alone.
The mineral samples included in this collection are biotite, calcite,
fluorite, galena, graphite, gypsum, hematite, magnetite, pyrite, and
quartz.
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Biotite
(Ferromagnesian potassium; hydrous aluminum silicate)
Color: black, green-black, or brown-black
Luster: nonmetallic
Hardness: 2.5-3 (soft)
Cleavage: excellent in one direction (breaks into thin sheets)
Streak: gray-brown
Distinctive properties: forms very short prisms that easily into very thin
flexible sheets
Economic uses: fire-resistant tiles, rubber, paint
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Calcite
CaCO3
(Calcium carbonate)
Color: usually colorless, white, or yellow, but may be green, brown, or pink;
opaque or transparent
Luster: nonmetallic
Hardness: 3 (soft)
Cleavage: excellent in three directions (breaks into rhombohedrons)
Streak: white
Distinctive properties: breaks into rhombohedrons; effervesces (fizzes)
in dilute hydrochloric acid (HCl)
Economic uses: used to make antacid tablets, fertilizer, cement; ore of
calcium
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Fluorite
CaF2
(Calcium fluoride)
Color: usually colorless, purple. blue, gray, green, or yellow; transparent to
translucent
Luster: nonmetallic
Hardness: 4 (soft)
Cleavage: excellent in four directions; breaks into octahedrons
Streak: white
Distinctive properties: crystals usually form as cubes
Economic uses: used extensively in the chemical industry in the
preparation of Hydrochloric acid (HCl); used as a flux in steel making; a
source of fluorine for processing aluminum
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Galena
PbS
(Lead sulfide)
Color: silvery gray
Luster: metallic
Hardness: 2.5 (soft)
Cleavage: good in three directions (breaks into cubes)
Streak: gray to dark gray
Distinctive properties: forms cubes and octahedrons; very heavy for its
size (has a high specific gravity)
Economic uses: ore of lead for TV glass, auto batteries, solder,
ammunition, paint
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Graphite
C
(Carbon)
Color: silvery gray to black
Luster: metallic
Hardness: 1 (very soft)
Cleavage: excellent in one direction
Streak: dark gray
Distinctive properties: forms flakes, short hexagonal prisms, and earthy
masses; greasy feel; very soft
Economic uses: used as a lubricant (graphite oil), pencil leads, fishing rods
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Gypsum
CaSO4·2H2O
(Calcium sulfate)
Color: colorless, white, or gray
Luster: nonmetallic
Hardness: 2 (very soft)
Cleavage: good
Streak: white
Distinctive properties: forms tabular crystals, prisms, blades, or needles
Economic uses: plaster-of-paris, wallboard, drywall, art sculpture medium
(alabaster)
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Hematite
Fe2O3
(Iron oxide)
Color: silvery gray, black, or brick red
Luster: metallic or nonmetallic
Hardness: 1.5-6 (soft to hard)
Cleavage: none
Streak: red to red-brown
Distinctive properties: nonmetallic varieties are soft and metallic
varieties are hard, but both have the same color streak; forms thin
tabular crystals
Economic uses: red pigment; ore of iron for steel tools, vehicles, nails,
bolts, bridges, etc.
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Magnetite
Fe3O4
(Iron oxide)
Color: silvery gray to black
Luster: metallic
Hardness: 5.5-6.5 (hard)
Cleavage: none
Streak: dark gray
Distinctive properties: magnetic; crystals are octahedral in shape
Economic uses: ore of iron for steel, brass, bronze, tools, vehicles, nails
and bolts, bridges, etc.
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Pyrite
FeS2
(Iron sulfide)
Color: brass yellow
Luster: metallic
Hardness: 6-6.5 (hard)
Cleavage: no cleavage
Streak: dark gray
Distinctive properties: forms cubes or octahedrons; nickname: fools gold
Economic uses: ore of sulfur, sulfuric acid, explosives, fertilizers, pulp
processing, and insecticides
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Quartz
SiO2
(Silicon dioxide)
Color: usually colorless, white, or gray but uncommon varieties occur in all
colors; transparent to translucent
Luster: nonmetallic
Hardness: 7 (hard)
Cleavage: none
Streak: white
Distinctive properties: forms hexagonal prisms and pyramids
Economic uses: used as an abrasive; used to make glass, gemstones
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Igneous
Rocks
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Igneous Rock Information
Basalt, granite, kimberlite, obsidian, pumice, and scoria are the
igneous rocks included in this collection. The following information is
useful in identifying igneous rocks.
• Igneous rocks form when magma or lava cool to a solid state, which
can occur at the Earth’s surface or within the Earth’s crust. The
origin refers to where the lava actually cooled. Igneous rocks that
form at the Earth’s surface are usually violently ejected from
volcanoes and are called extrusive igneous rocks. Igneous rocks can
also form within the Earth’s crust when a body of magma pushes its
way into the crust and cools. These types of igneous rocks are
called intrusive igneous rocks.
• The formation condition refers to the type of lava/magma and how
fast it cooled. The condition under which the rock formed is
directly responsible for the resulting texture.
• The texture of an igneous rock describes the sizes, shapes, and
arrangements of the various minerals that comprise the rock. The
size of the mineral crystals in an igneous rock can be an indicator
of how long it took the lava or magma to cool, and of which types of
chemicals were available during the cooling process. Large crystals
require a long time to grow, so their presence generally means that
a body of molten rock took a long time to cool. Tiny crystals, or
none at all, usually mean that the molten rock cooled quickly.
• Light colored minerals (quartz, plagioclase feldspar, potassium
feldspar, and muscovite) are called felsic minerals. Darker colored
minerals (biotite, amphibole, pyroxene, and olivine) are called mafic
minerals. The color index is the percentage of mafic (dark colored)
minerals in the igneous rock, and is a property often used to
classify igneous rocks.
• The mineralogical composition of an igneous rock is a description
of the kinds and abundances of the minerals that compose the
rock. Eight minerals make-up most igneous rocks: quartz, potassium
feldspar, plagioclase feldspar, muscovite, biotite, amphibole,
pyroxene, and olivine.
• The rock’s field features refer to how the specific igneous rocks
commonly appear in the field (in nature).
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Basalt
Origin: extrusive; forms at or near the Earth’s surface
Formation conditions: rapid cooling of fluid (runny) lava
Texture: crystals less than 1 mm (this is called aphanitic texture)
Color: dark gray to black
Hardness: 5-6 (hard)
Mineralogical composition: mafic
Field features: Basalt is one of the most widespread volcanic rocks. It
occurs in massive lava flows and can be thousands of feet thick.
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Granite
Origin: intrusive; forms at depth in the Earth’s crust.
Formation conditions: slow cooling of viscous (thick) magma
Texture: crystals range from 1 to 10 mm in size (this is called phaneritic
texture)
Color: depends on the abundance of feldspar minerals present and the
ratio of light to dark minerals; can be white to gray, dark gray, pink, flesh
colored, or red.
Hardness: generally greater than 5.5 (hard)
Mineralogical composition: more felsic minerals than mafic minerals
Field features: granite bodies are characteristically block-jointed on a
large scale, making it easier to remove the rock for mining.
Economic uses: Due to its great crushing strength, resistance to
weathering, and ability to polish nicely, granite is used for architectural
construction, ornamental stone, and for monuments; some types of
granite are also used as fertilizer
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Kimberlite
Origin: intrusive; forms at depth in the Earth’s crust.
Formation conditions: slow, then rapid cooling and/or a change in the
magma thickness or composition
Texture: large and small crystals (this is called porphyritic texture)
Color: grayish green to bluish gray
Hardness: highly variable
Field features: generally occur as ancient volcanic structures
Economic uses: Kimberlite, particularly from South Africa, has become a
prime source for the world’s gem quality diamonds.
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Obsidian
“Volcanic glass”
Origin: extrusive; forms at the Earth’s surface. It is actually glass rather
than an aggregate of minerals.
Formation conditions: rapid cooling- the magma solidifies before any
minerals can develop and crystallize
Texture: glassy (no crystals present)
Color: generally black but more or less smoky with transparent to
translucent edges; other colors can be gray, reddish brown, mahogany, or
dark green; black is sometimes mixed with any of these colors to form
thin bands or produce a marbled effect
Hardness: 6-7 (scratches glass)
Mineralogical composition: can range from felsic to mafic
Field features: Obsidian occurs as thick, black, glassy lava flows of
limited area.
Economic uses: Obsidian was once chipped and flaked into knives,
spearheads, and many other implements with razor sharp edges.
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Pumice
Origin: extrusive; forms at or near the Earth’s surface
Formation conditions: rapid cooling of lava filled with gas bubbles (the
lava cools before most of the gases have time to escape, thus the gases
are trapped in the rock, making it very light weight)
Texture: vesicular, foamy, frothy, very light weight, very porous (includes
lots of air spaces)
Color: light gray, white
Hardness: 6-6.5 (hard)
Mineralogical composition: felsic
Field features: Occurs as ejected material from explosive volcanoes or as
a crust on lava flows.
Economic uses: foot scrubbing stones, used to “stone wash” denim, an
abrasive, lightweight aggregate
Special properties: light enough to float in water
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Scoria
Origin: extrusive; forms at or very near the Earth’s surface
Formation conditions: rapid cooling of lava filled with gas bubbles; the
vesicles are formed by the expansion of gases trapped in the cooling lava.
Texture: vesicular; contains many vesicles, or hollow places where gases
were once trapped.
Color: dark brown, reddish rust, dark gray to black
Hardness: 5-6 (hard)
Mineralogical composition: mafic
Field features: Scoria is generally found near the top of basalt lava flows.
Economic uses: little economic use, although often used in flowerbeds
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Metamorphic
Rocks
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Metamorphic Rock Information
Metamorphic rocks are rocks changed from one form to another by
intense heat, extreme pressure, or the action of hot fluids. A good way
to understand the process of metamorphism is to think about how it
occurs in your home. Heat can be used to metamorphose bread into toast,
pressure can be used to crush an aluminum can into a more compact form,
and the chemical action of hot fluids can be used to change raw veggies
into cooked veggies. Metamorphic rocks are classified by identifying the
rocks’ textural features and mineral compositions, as well as other
distinctive features.
Anthracite coal, gneiss, marble, phyllite, schist, slate, and quartzite are
included in this collection. Information about the texture, color,
hardness, metamorphism, parent rock, and economic uses are important in
the analysis and classification of metamorphic rocks.
•
•
•
Two main groups of metamorphic rocks can be distinguished on the
basis of their characteristic textures, foliated and nonfoliated.
Foliated metamorphic rocks exhibit foliations, which are parallel
layers of minerals that have been aligned due to pressure and
recrystallization. Nonfoliated metamorphic rocks lack foliations.
Details of a rock’s particular metamorphic process are described
under the category of “metamorphism”.
Since metamorphic rocks are transformed versions of preexisting
rocks, all metamorphic rocks have a parent rock. Parent rocks, the
rocks that underwent metamorphism, can be any of the three rock
types: igneous rocks, sedimentary rocks, and metamorphic rocks.
Parent Rock Type
Sedimentary
Igneous
Metamorphic
Parent Rock
Limestone
Shale
Sandstone
Crystalline
Rocks
Slate
Phyllite
Schist
Intense Heat
Intense Pressure
Hot Fluids
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Resulting
Metamorphic Rock
Marble
Slate
Quartzite
Gneiss
Phyllite
Schist
Gneiss
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Anthracite Coal
Texture: nonfoliated; smooth
Color: glossy or shiny black
Hardness: 2-2.5 (soft)
Metamorphism: anthracite coal is formed from the extremely high
temperatures and pressures present at a deep burial depth
Parent rock: bituminous coal
Economic uses: used primarily as domestic fuel because of its smokeless
quality and relatively high energy output, but is also the most expensive
coal
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Gneiss
Texture: foliated; medium to coarse grained; gneissic banding: minerals
segregated into alternating layers give the rock a banded texture
Color: the rock consists of alternating bands of light and dark; the light
layers can be gray, tan, or pink and the dark layers can be gray or black
Hardness: light layers, 6-7; dark layers, 2.5-3
Metamorphism: forms at temperatures ranging from 450ºC to 700ºC and
correspondingly high pressures
Parent rock: schist
Economic uses: construction stone, decorative stone, source of gemstones
such as rubies
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Marble
Texture: nonfoliated; sandy texture
Color: The normal color is white but accessory minerals result in black,
green, yellow, brown, or red. An uneven distribution of these coloring
minerals often results in color blotches or produces a vein-like effect
called “marbled.”
Hardness: 3 (soft)
Parent rock: limestone or dolomite
Economic uses: art carvings, construction stone, decorative stone, source
of lime for agriculture, concrete aggregate
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Phyllite
Texture: foliated; wavy foliations
Color: medium to dark gray to black; occasionally green, red, purple,
brown, or yellow
Hardness: easily scratched with a knife blade
Metamorphism: Phyllite is an intermediate stage in the metamorphic
series:
Shale→ Slate→ Phyllite→ Schist→ Gneiss. As each rock in the series is
metamorphosed, it transforms into the rock listed to the right of it in
the series. Thus, each rock’s parent rock is the rock to its left.
Parent rock: slate
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Schist
Texture: foliated
Color: silvery white, all shades of gray, sometimes with yellow to brown
tones.
Hardness: varies greatly depending on the proportion of hard to soft
minerals
Metamorphism: Schist is near the end of the metamorphic series:
Shale→ Slate→ Phyllite→ Schist→ Gneiss. As each rock in the series is
metamorphosed, it transforms into the rock listed to the right of it in
the series. Thus, each rock’s parent rock is the rock to its left.
Parent rock: Phyllite
Economic uses: building stone, minor source of minerals of economic value
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Slate
Texture: foliated
Color: medium to dark gray to black; occasionally green, red, purple,
brown, or yellow
Hardness: easily scratched with a knife blade
Metamorphism: Slate is the second rock formed in the metamorphic
series:
Shale→ Slate→ Phyllite→ Schist→ Gneiss. As each rock in the series is
metamorphosed, it transforms into the rock listed to the right of it in
the series. Thus, each rock’s parent rock is the rock to its left.
Parent rock: mudstone and shale
Economic uses: roofing slate, blackboards, tabletops, floor tile, and
decorative stone
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Quartzite
Texture: nonfoliated; sandy texture; fine to medium grain sizes
Color: white, light to dark gray, or brownish to pinkish
Hardness: 7; tough but brittle
Metamorphism: quartz and sand grains are fused together; grains will not
rub off like sandstone
Parent rock: sandstone
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Sedimentary
Rocks
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Sedimentary Rock Information
Sediments are loose grains and chemical residues of rock fragments,
mineral grains, parts of plants and animals, and rust. Sediments are
usually produced by organic processes or by physical or chemical
weathering. Both weathering processes result in larger objects being
broken down into smaller particles, or sediments. Sedimentary rocks are
formed when sediments are compressed together (compaction) or
hardened (cementation), or when crystals form from solutions
(precipitation).
Bituminous coal, conglomerate, coquina, limestone, sandstone, and shale
are included in this collection. To correctly identify and analyze
sedimentary rocks, Geologists gather information about the textures,
origins, and compositions of the rocks.
•
•
•
The texture of a sedimentary rock is a description of its
constituent parts and the sizes, shapes, and arrangement of those
parts. Grain sizes can range from gravel (the largest) to sand to
silt to clay (the smallest). The shape of the grains can vary, with
some grains being very angular and others being more rounded.
Many times sediments are sorted by things such as wind or water
(ex: larger and thus heavier grains will settle to the bottom of a
river more quickly than smaller particles). The arrangement of a
sedimentary rock describes whether the rock is poorly sorted (all
grain sizes mixed together) or well sorted (all grain sizes sorted by
size).
Sedimentary rocks are biochemical, chemical, or detrital in origin.
Biochemical sediments and rocks are composed mainly of the
remains of organisms such as shells, plant fragments, or carbon.
Chemical sediments and rocks are composed mainly of crystals that
have precipitated from solutions. Detrital sediments and rocks are
composed mostly of detrital grains, or worn rock and mineral grains
that were weathered and transported from their sources.
The composition of a sedimentary rock describes which grains in
particular actually comprise the rock.
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Bituminous Coal
Texture: dense and brittle or porous and sooty
Color: black
Hardness: 2 (soft)
Origin: biochemical (comprised mostly of the remains of organisms)
Composition: the elements carbon, hydrogen, and oxygen with some sulfur
and nitrogen; also, plant fragments or charcoal
Economic uses: Coal is the most abundant fossil fuel in the world, and
bituminous coal occurs in the greatest quantities. It has the highest
caloric heat value, but burns with a yellow flame and gives off a
bituminous odor.
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Conglomerate
Texture: rounded rock fragments of pebble, cobble, or boulder size (2mm
to 25cm or more in diameter)
Color: varies greatly depending on the rock fragments contained in the
conglomerate
Hardness: highly variable
Origin: detrital (comprised mostly of pieces of preexisting rocks)
Composition: mainly quartz grains, feldspar grains, rock fragments, and
clay minerals
Economic uses: limited use as concrete aggregate
Other properties: may contain fossils
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Coquina
“Skeletal limestone”
Texture: gravel sized grains (greater than 2 mm); visible fossil shells
Color: tan, yellowish brown, pale brown
Hardness: 3-4 (soft)
Origin: biochemical (comprised mostly of the remains of plants and
animals)
Composition: composed mainly of marine or freshwater mollusk shells and
shell fragments cemented together with calcium carbonate, CaCO3
Other properties: effervesces in dilute hydrochloric acid
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Limestone
“Chemical limestone”
Texture: crystals are coarse-grained (greater than 2 mm) to fine-grained
(0.0039 mm)
Color: white or light to dark gray to black
Hardness: 3-4 (soft)
Origin: chemical (comprised mostly of mineral crystals precipitated from
aqueous solutions)
Composition: mainly calcium carbonate, CaCO3
Economic uses: interior and exterior structural purposes, the
manufacture of mortar and Portland cement, flux in iron and steel
smelting operations, and concrete aggregates.
Other properties: effervesces in dilute hydrochloric acid (HCl)
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Sandstone
Texture: sand sized grains (0.05mm to 2 mm in size) held together by
compaction into clay or through cementation by silica, carbonates, clay, or
iron oxides
Color: extremely varied
Hardness: variable
Origin: detrital (comprised mostly of pieces of preexisting rocks)
Composition: mainly quartz grains, feldspar grains, rock fragments,
and/or clay minerals
Economic uses: construction uses; some varieties of sandstone have been
used as a source of potash for use in fertilizer
Other properties: sandstones usually have a gritty feel
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Shale
“Mudstone”
Texture: particles of silt size (microscopic) and clay size (submicroscopic)
Color: light to dark gray; sometimes buff, brown, reddish brown, or deep
red
Hardness: easily scratched by a knife (soft)
Origin: detrital (comprised mostly of pieces of preexisting rocks)
Composition: mostly clay minerals
Economic uses: the manufacture of bricks, pottery, and other ceramic
products. Oil shales represent a great potential supply of fossil fuel.
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Complete Rock and Mineral
Collection
From left to right:
Top row: (Minerals) biotite, calcite, fluorite, galena, graphite, gypsum,
hematite, magnetite, pyrite, and quartz.
Second row: (Igneous rocks) basalt, granite, kimberlite, obsidian, pumice,
and scoria.
Third row: (Metamorphic rocks) anthracite coal. gneiss, marble, phyllite,
schist, slate, and quartzite.
Bottom row: (Sedimentary rocks): bituminous coal, conglomerate, coquina,
limestone, sandstone, and shale.
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Sources:
Busch, R.M., Ed., 2000, Laboratory Manual in Physical Geology: Prentice
Hall, New Jersey, 276 p.
Chesterman, C.W., 1998, National Audubon Society Field Guide to North
American Rocks and Minerals: Alfred A. Knopf, New York, 850 p.
WARD’S Natural Science Establishment, Inc. (All rock samples are from
WARD’S)
Prepared by:
Ashley Phillips
NSF NMGK-8
University of Mississippi
July 2004
NSF North Mississippi GK-8
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