Rock And Mineral Identification

Front 1

Color: black
Streak: none
Texture: very smooth with sharp edges,breaks with a conchoidal fractures
Shiny: glassy
Other: formed from lava, known as "nature's glass"

Back 1

Obsidian

Front 2

Color: light gray
Texture: full of small similar-sized air bubbles "frothy"
Shiny: light sheen, not glossy
Other: floats in water, very light

Back 2

Pumice

Front 3

dark-colored with abundant round bubble-like cavities known as vesicles. It ranges in color from black or dark gray to deep reddish brown.

Many people believe that small pieces of it look like the ash produced in a coal furnace. The thick walls of this rock can make it sink in water

Back 3

Scoria

Front 4

dark-colored, fine-grained

Back 4

Basalt

Front 5

light-colored, fine-grained, extrusive rock that typically contains quartz and feldspar minerals.

Back 5

Rhyolite

Front 6

light-colored rock with grains large enough to be visible with the unaided eye. It is composed mainly of quartz and feldspar with minor amounts of mica, amphiboles and other minerals. This mineral composition usually gives it a red, pink, gray or white color with dark mineral grains visible through it

Back 6

Granite

Front 7

What Igneous rock is this?

Back 7

Granite

Front 8

rough rock, contains shells

Back 8

Coquina

Front 9

composed of small-sized grains of mineral, rock or organic material. It also contains a cementing material that binds the grains together and may contain a matrix of silt- or clay-size particles that occupy the spaces between the grains. feels like sand paper

Back 9

Sandstone

Front 10

Texture: fine grained, sandpapery feel
Shiny: dull

Back 10

Sandstone

Front 11

Visible angular gravel grains
rock feels gritty

Back 11

Breccia

Front 12

Rock feels gritty and bumpy
Visible Rounded gravel grains
Shine: dull

Back 12

Conglomerate

Front 13

coarse-grained, intrusive rock
composed primarily of plagioclase feldspar, amphibole, and pyroxine minerals with small amounts of biotite mica. It typically contains very little quartz.

abundant white and dark minerals - a “salt and pepper” appearance.

Back 13

Diorite

Front 14

Mineral
Color Typically off-white or shades of red, orange and brown, occasionally green.
Cleavage One perfect cleavage and one good cleavage that meet at nearly 90°
Hardness 6 (harder than glass)
Specific Gravity 2.6
Luster Crystals are vitreous (glass-like) to porcelaneous (porcelain-like)
Streak White

Back 14

Potassium Feldspar

Front 15

Mineral
Color Typically white to gray, may also range from colorless, through shades of off-white, to yellowish, pink, reddish brown or nearly black.
Cleavage One perfect cleavage and one good cleavage that meet at nearly 90°
Hardness 6 to 6.5 (harder than glass)
Specific Gravity Increases from 2.6 to 2.8 depending on amount of calcium
Luster Crystals are vitreous (glass-like) to porcelaneous (porcelain-like)
Streak White
Special Features Common twinning in the crystal structure that creates fine parallel grooves or striations on some cleavage surfaces.

Back 15

Plagioclase Feldspar

Front 16

Mineral
Color Colorless or transparent when pure, but color may be extremely variable due to the presence of slight chemical impurities. The most common variety is violet, but may also be yellow, green, white, blue, gray, black or exhibit a variety of colors in zones or bands.
Cleavage Perfect cleavage in four directions to produce octahedrons, brittle
Hardness 4 (relatively soft)
Specific Gravity 3.0-3.3 (average ‘weight’)
Luster Crystals are vitreous (glass-like)
Streak White
Other: Breaks in triangular shape

Back 16

Fluorite

Front 17

Mineral
Color Usually colorless, white or silver, occasionally yellow or brown.
Cleavage single perfect cleavage to produce thin sheets or flakes.
Hardness 2 to 2.5 (very soft)
Specific Gravity 2.8-3 (feels slightly lighter than expected for sample size)
Luster vitreous (glass-like) to pearly, crystals are transparent to translucent and usually occur as thin flakes or thicker ‘books’ of many flakes thickness.
Streak White

Back 17

Muscovite

Front 18

Mineral
Color typically brown to black.
Cleavage Single perfect cleavage to produce thin flexible sheets or flakes.
Hardness 2.5 to 3 (soft)
Specific Gravity
Luster Pearly to submetallic, crystals are translucent and usually occur as thin flakes or as thicker ‘books’ of sheets.
Streak White to gray

Back 18

Biotite

Front 19

Mineral
Color: Usually clear or white, but small amounts of impurities may give a red or orange hue and bacterial impurities can create a variety of pastel colors
Three perfect cleavages at right angles to produce cubes
2.5 (soft)
2.1 (up to 2.6) (feels rather light)
Crystals are vitreous (glass-like), massive form is dull
Streak: White

Back 19

Halite

Front 20

mineral
Color Colorless, white, pale green, bright emerald-green to dark green, brown, gray
Cleavage Perfect cleavage on 001
Hardness 1
Comments Flexible but not elastic. Feels slippery or greasy to the touch.
Luster Sub-Vitreous, Resinous, Waxy, Greasy, Pearly
Streak White

Back 20

Talc

Front 21

Mineral
Color Lead gray
Cleavage Perfect cleavage in three directions, forming cubes; brittle nature
Hardness 2.5 (about as hard as a fingernail)
Specific Gravity 7.4-7.6 (feels ‘heavy’, even for a metallic mineral)
Luster Metallic, opaque, Shiny
Streak Lead gray

Back 21

Galena

Front 22

Mineral
Color Pale olive green to yellow-green, occasionally brown
Cleavage Poor cleavage in two directions at 90o
Hardness 6.5 to 7 (very hard)
Specific Gravity 3.2 (Mg-rich variety) to 4.3 (Iron-rich variety) (average weight)
Luster Massive or transparent to translucent crystals with a glassy luster
Streak White

Back 22

Olivine

Front 23

Mineral
Color Variable, with dark red to reddish brown being the most common, but varieties may be red-violet, brown, black emerald green, or even white
Cleavage None
Hardness 6.5 – 7.5 (very hard)
Specific Gravity 3.6 – 4.3 (increases with iron content)
Luster Vitreous (glass-like) to resin-like, transparent to translucent
Streak white (or pale shade of sample’s color)

Back 23

Garnet

Front 24

Mineral
Color Transparent to translucent crystals are colorless, white or light-colored; massive forms are typically buff, gray, or white.
Cleavage perfect cleavage in three directions to produce rhombohedra/Parallelogram
Hardness 3 (down to 2.5 on some surfaces) – easily scratched by a metal nail, but too hard to be scratched by a fingernail.
Specific Gravity 2.7 (feels relatively light) (3.0 for aragonite)
Luster crystals are vitreous (glass-like) but cloudy, massive form is dull
Streak White

Back 24

Calcite

Front 25

Mineral
Color Usually clear or white, but minor impurities can create a variety of colors. Crystals are most commonly hexagonal prisms, whose pyramid-like ends often line the faces of open voids. Cryptocrystalline varieties are most often massive.
Cleavage Does not exhibit cleavage, although crystal faces may be mistaken for cleavage planes. Conchoidal fracture is characteristic of both macrocrystalline and cryptocrystalline varieties.
Hardness 7 (very hard) will cut glass
Specific Gravity 2.6 to 2.65 (macrocrystalline varieties)
(Microcrystalline varieties)
Luster Crystals are vitreous (glass-like), massive form is dull or waxy.
Streak White

Back 25

Quartz

Front 26

Mineral
"Fools Gold"
Color Pale brassy yellow, will tarnish to darker hues that may be iridescent
Cleavage None, conchoidal fracture
Hardness 6 – 6.5, brittle nature
Specific Gravity 5 or above (feels heavier than average, even for a metallic mineral)
Luster Metallic, opaque. May exhibit faint striations (lines) on some crystal and cleavage faces
Streak Greenish black or brownish black

Back 26

Pyrite

Front 27

Magnetic Mineral
Color Black
Cleavage None, brittle
Hardness 5.5 – 6.5 (harder than glass)
Specific Gravity 5.2 (feels heavy compared to most rock-forming minerals, but about the same as other metallic minerals)
Luster Metallic to dull, opaque
Streak Black

Back 27

Magnetite

Front 28

Mineral
Color Black to silver gray, in earthy forms is red to brown
Cleavage None
Hardness 5 - 6 (hard) in most varieties, but earthy variety is very soft (<2)
Specific Gravity 5.3 (feels heavy, average for a metallic mineral)
Luster wide range from splendent metallic to dull earthy
Streak red brown to rusty red

Back 28

Hematite

Front 29

Mineral
Color Usually white, colorless or gray in massive form, crystals are clear, transparent to translucent. If impurities are present, gypsum may also appear to be red, brown or yellow.
Cleavage Good cleavage in one direction, only fair in two others to produce thin rhombic fragments.
Hardness 2 (very soft)
Specific Gravity 2.3 (feels rather light)
Luster Crystals are vitreous (glass-like) to pearly, massive form is dull
Streak White

Back 29

Gypsum

Front 30

What igneous rock is this?

Back 30

Scoria

Front 31

consisting of large-grained crystals, such as feldspar or quartz, dispersed in a fine-grained feldspathic matrix or groundmass

Back 31

Porphyry

Front 32

coarse-grained, dark-colored, intrusive rock. It is usually black or dark green in color and composed mainly of the minerals plagioclase and augite.

Back 32

Gabbro

Front 33

foliated rock that has a banded appearance and is made up of granular mineral grains. It typically contains abundant quartz or feldspar minerals.

Back 33

Gneiss

Front 34

rock with well developed foliation. It often contains significant amounts of mica which allow the rock to split into thin pieces.

Back 34

Schist

Front 35

What Metamorphic rock is this?

Back 35

Schist

Front 36

Harder than glass, non-foliated rock that is produced by the metamorphism of sandstone. It is composed primarily of quartz.

Back 36

Quartzite

Front 37

fine-grained, foliated rock
Most are gray in color and range in a continuum of shades from light to dark gray. It also occurs in shades of green, red, black, purple and brown
can be black, gray, brownish red, bluish gray, or greenish gray. It is very fine grained and has thin, quite smooth, flat layers. Unlike shale, slate easily splits into thin flat pieces. It often will scratch glass, with a little difficulty.- makes a THUD sound

Back 37

Slate

Front 38

low hardness and solubility, sually a light-colored rock. When it is formed from a limestone with very few impurities it will be white in color. If this rock contains impurities such as clay minerals, iron oxides or bituminous material can be bluish, gray, pink, yellow or black in color

Back 38

Marble

Front 39

What Metamorphic rock is this?

Back 39

Marble (pink marble)

Front 40

usually very soft. typically gray, bluish, green or brown in color, often variegated. Feels slimy and greasy

Back 40

Soapstone

Front 41

What is the difference between basalt and gabbro?

Back 41

The difference between basalt and gabbro is that basalt is a fine-grained rock while gabbro is a coarse-grained rock.

Front 42

It has a bright luster and breaks with a semi-conchoidal fracture, color is black, streak color is black to brownish black

Back 42

Anthracite Coal

Front 43

typically a banded rock. In this photo you can see bright and dull bands Its coloration can be black or sometimes dark brown; often there are well-defined bands of bright and dull material within the seams
streak is black to brownish black

Back 43

Bituminous coal

Front 44

you can scratch with finger, very soft

Back 44

Gyprock

Front 45

What Does It Look Like? may be black, gray, red, brown, dark green, or blue. It is fine grained, so particles usually can not be seen. When moistened, usually smells like wet mud. Makes a CLIPPY NOISE when tapped

Back 45

Shale

Front 46

looks like a mixture of sand and different sizes of rounded pebbles. The pebbles are the important observation.

Back 46

conglomerate

Front 47

What rock is this?

Back 47

Rhyolite

Front 48

What Rock is this.. layes tend to be flaky

Back 48

Schiest

Front 49

What rock is this?

Back 49

Gneiss