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Geology Rocks and Minerals

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sphalerite: NM; 3.5-4 Hardness; no cleavage; dark brown-->black; light yellow streak; cubic habit; sulfuric smell
Mineral
Gypsum: NM; 2 Hardness; Basal Cleavage; translucent white; white streak; scratch with fingernail
Mineral
Galena: Metallic; 2.5 Hardness; Cubic cleavage; light gray/silver; grey-black streak; very dense; sulfuric smell; not magnetic
Mineral
Augite: NM; 5.5 Hardness; Prismatic (2D cleavage); Dark green-gray; white streak; glossy; cleavage planes: 93 and 87; Chemical Formula (Ca,Na)(Mg,Fe,Al,Ti)(SiAl)2)O6
Mineral
Quartz: NM; 7 Hardness; Conchoidal fracture; Clear, purple; no streak; hexagonal habit; Chemical Formula: SiO2
Mineral
Halite: NM; 2.5 hardness; Cubic cleavage; Clear; white streak; breaks into cubes; salty taste; cubic crystal habit; Chemical Formula: NaCl
Mineral
Olivine: NM; 7 Hardness; Conchoidal Fracture; Green w/dark speckles; white streak; sandy texture; small crystals; Chemical Composition: (Fe,Mg)2SiO4
Mineral
potassium feldspar: NM (glossy); 6.5 Hardness; Cubic Cleavage; light pink; no streak; light pink with lighter white part; Chemical Formula: KAlSi3O8
Mineral
Pyrite: Metallic; 5.5 Hardness; no cleavage; bronze-gold; no streak; shiny
Mineral
Epidote: NM; 6.5 hardness; no cleavage; green, brown, black, white; no streak; shiny
Mineral
Kaolinite: NM; 2.5 hardness; no cleavage; white with white streak; chalk-like; Chemical Formula: Al4(Si4O10)(OH)8
Mineral
Azurite: NM; 2.5-4.5 Hardness; no cleavage; blue-brown (light); blue streak; non magnetic
Mineral
Kyanite: NM; 4.5 Hardness; No cleavage; green, blue, gray; white streak; blades (blue)
Sulfur: NM; 1.5-2.5 Hardness; no cleavage; yellow; pale yellow streak; sulfuric smell
Element/Mineral
Hornblende (amphibole): NM; 5.5-6.5 Hardness; prismatic cleavage at 56 and 124 degrees; dark gray; light gray streak; striations; Chemical Formula Ca2(Mg,Fe)4Al(Si2Al)O22(OH,F)2
Mineral
Calcite: NM; 2.9 Hardness; cubic cleavage; white and translucent; white streak; effervesces; Chemical Formula: CaCO3
Mineral
Talc: NM; less than 2.5 hardness; no cleavage; light tan-->white; white streak; soapy feel; scratch with fingernail
Mineral
Fluorite: NM; 4.5-5.5 hardness; 4 dimensional cleavage; green, blue, white, brown; white streak
Mineral
Garnet: NM; 6.5 Hardness; no cleavage; some parting; dark red-black; no streak; opaque with translucent red; fractured/parting
Biotite Mica: NM; less than 2.5 Hardness; Basal Cleavage; Bronzey-brown; green streak; brittle, comes off in sheets; peels off
Mineral
Tourmaline: NM, greater than 5.5 less than 6.5 hardness; poor cleavage; gray-black; black streak; waxy; non-metallic; striations
Mineral
Hematite: Metallic; 5.5-6.5 hardness; no cleavage; dark metallic gray; light brown streak; slightly magnetic
Mineral
Corundum: NM; 9 hardness; no cleavage; brown-gray; no streak; hexagonal habit; striated ends
Mineral
Dolomite: NM; 2.9 Hardness; no cleavage; opaque off-white; white streak; sandy; effervesces when powdered; Chemical Formula CaMg(CO3)2
Mineral
Graphite: Metallic; 2.5 or less hardness; no cleavage; silver; silver-black streak
Mineral
Plagioclase Feldspar: NM; 6 Hardness; Prismatic cleavage (angles about 90 degrees); dark gray with some green; no streak; looks like oil on water in places (oil marks); Chemical Formula: NaAlSi3O8
Mineral
Muscovite Mica: NM; less than 5.5 hardness; Basal Cleavage; translucent copper clear sheets; light gray streak; breaks off into thin translucent sheets; Chemical Formula: KAl2(AlSi3O17)(OH,F)2
Mineral
Staurolite: NM; greater than 6.5 hardness; no cleavage; dark brown; no streak; penetrating twinning; six-sided structure
Mineral
Chlorite: NM; greater than 6.5 hardness; excellent basal cleavage; transparent green with dark spots; clear flakes; streak is flakes; clean clear sheets
Not on list
Apatite: NM; 5 hardness; conchoidal fracture; lemon yellow or green; white streak; hexagonal; bubbles
Mineral
Gabbro: Phaneritic; Mafic; Has Augite and Plagioclase feldspar in it
Igneous
Pumice: Glassy/Vesicular; not felsic or mafic
Igneous
Breccia: Pyroclastic
Sedimentary
Diorite: Phaneritic; Intermediate; Plagioclase Feldspar, Hornblende and Augite
Igneous
OBsidian: Glassy
Igneous
Vesicular Basalt: Vesicular; Mafic; Plagioclase feldspar, hornblende and Augite
Igneous
Rhyolite: Aphanitic (fine grained); Felsic; Potassium Feldspar and quartz
Igneous
Granite: Phaneritic; Felsic; Potassium Feldspar and quartz
Igneous
Porphyritic Andesite: Porphyritic; Intermediate; Plagioclase feldspar
Igneous
Basalt; Aphanitic; Mafic; Olivine and Pyroxene
Igneous
Peridotite: Phaneritic; Ultramafic; Olivine and pyroxene
Not on list
Pegmatitic Granite: Phaneritic; Felsic; Potassium Feldspar and quartz
Igneous
Oolitic Limestone: Sedimentary; sand-size particles; bioclastic--> calcite; oolites; effervesces
Sedimentary
Siltstone/Mudstone; Sedimentary; Mud-sized particles; silicates and quartz
Sedimentary
conglomerate: Sedimentary; gravel-sized particles; detrital--> siliciclastic; rock pieces
Sedimentary
Greywacke Sandstone: sedimentary; Mud/sand sized particles; silicates
Sedimentary
Bituminous Coal: no particle size; carbon and organics; layered; shiny in spots; light
Sedimentary
Micrite Limestone: Sedimentary; mud sized particles; calcite; effervesces
Sedimentary
Dolostone: Sedimentary; mud-size particles; dolomite; effervesces when powdered
Sedimentary
Chert: Sedimentary; no particle size; microcrystalline; silicates; conchoidal fracture
Sedimentary
Fossilliferous Limestone: Sedimentary; sand-size particles; carbonate and calcite; shells/fossils
Sedimentary
Rock Gypsum: Sedimentary; no particle size; Gypsum
Mineral
Arkose Sandstone: Sand-size particles; feldspars and silicates
Sedimentary
Shale: mud-size particles; silicates; layered
Sedimentary
Coquina: gravel size particles; calcite and shell fragments; effervesces
Sedimentary
Ironstone: sand size particles; Hematite; iron-rich; red streak
Mineral
chalk: mud-size particles; calcite; effervesces
Quartzite: metamorphic; non-foliated; fine--> coarse grained; quartz; sandy--> grains don't come off; parent rock: Sandstone
Serpentinite: Non foliated; microcrystalline; green; glassy; conchoidal fracture; serpentine; Parent Rock: Basalt, Gabbro, Ultramafic igneous rocks
chlorite/green schist: foliates: schist-like; quartz; shiny; schistocity; scaly; Parent Rock: mudstone, shale, slate, phyllite
Gneiss: Foliated, banded; quartz; banding, color alternating layers, coarse-grained; Parent Rock: Granite
Anthracite Coal: Non-Foliated; fine-grained; Light, glassy, conchoidal fracture; Parent Rock: Peat, Lignite, Bituminous Coal
Hornfels: Non-Foliated; Microcrystalline; hard, dark, sparkly; contact metamorphism; Parent Rock: Any Rock
Phyllite: Foliated; Schist-like; dark, hard, shiny, phyllitic texture; Parent Rock: mudstone, shale, slate
Soapstone: Non-foliated; microcrystalline; soft, can scratch with fingernail; Parent Rock: Basalt, Gabbro, Dolostone, Ultramafic igneous rocks
Slate: Foliated; no visible grains; shingle-like; flat, slatey, breaks into sheets, cleavage; Parent Rock: Mudstone or Shale
Amphibolite: Foliated or Non-foliated; medium--> coarse-grained; glossy black; blade-like crystals; Parent Rock: Basalt, Gabbro, Ultramafic igneous rocks
Muscovite/Mica Schist: Foliated; medium--> coarse-grained; schist-like; porphyroblasts--> staurolite; Parent Rock: mudstone, shale, slate
Albite
White,tan, or cream feldspar
Hardness:6-6.5
Specific gravity:2.6-2.63
Streak:white
Color: many eps. White
Group: silicates
Crystal shape: monoclinic
Almandine
H:6.5-7.5, S.G:4.31. Color deep purplish red. Usually found in metamorphic rock.

a deep red garnet consisting of iron aluminum silicate
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Amazonite
Bright green feldspar
Hardness: 6-6.5
Streak: white
Color: medium ESP. Green
Group: silicates
Crystal shape: triclinic
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Aragonite
white, powdery variety of calcite. can often form amber-colored hexagonal crystals
hardness:3.5-4
specific gravity: 2.54-2.95
streak: white
color; many
group: carbonates
crystal shape: orthorhambic
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Bauxite
a clay-like mineral, H 1-3 S.g 2-2.5 Luster: dull

It is the main ore for production of aluminum. Note the obvious nodules.
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Barite
H 3-3.5 S.G. 4.3-4.6 Streak: White, Color: white or colorless mineral (BaSO4). Can be bluish, yellow, brown or reddish. A heavy mineral that can be recognized by its specific gravity (SG). Quartz is harder and not as heavy
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Bornite
Cu5FeS4

H 3.0, S.G. 5.06-5.08 Streak: gray-black Luster: metallic

This beautiful purplish iridescence helps to identify this copper mineral . Sometimes called peacock ore. Untarnished bornite is golden colored

a mineral consisting of sulfides of copper and iron that is found in copper deposits
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Celestite
usually a soft, translucent white or blue
hardness:3-3.5
specific gravity:3.96-3.98
streak:white
color;light
group:sulfates
crystal shape:othorhombic
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Chalcopyrite
Metallic. H = 3.5 - 4. Streak: dark gray. Color bright silvery gold, tarnishes bronze, brassy gold or iridescent blue-green and red; brittle; No cleavage. Forms dense masses or elongate tetrahedrons.
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Copper
H: 2.5-3, S.G 8.94, Streak: Black, Luster: Metallic. Native copper looks how we think copper should look. Major deposits of native copper in Keweenaw Peninsula in Michigan.
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Diamond
native crystalline carbon that is the hardest known mineral, that is usually nearly colorless, that when transparent and free from flaws is highly valued as a precious stone, and that is used industrially especially as an abrasive; also : a piece of this substance
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Goethite
hardness:5-5.5
specific gravity:3.3-3.4
streak:orange-brownish
color:black-brown light
group:hydroxides
crystal shape:othorhombic
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Gold
a soft yellow malleable ductile (trivalent and univalent) metallic element
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Lepidolite
Hardness:2.5-4
Heft: 2.8
Color:Pink, lilac, purple
Streak: white, grey
Breakage: cleavage in two directions
Luster: nonmetallic (vitreous)
Other:small crystals and flaky
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Magnetite
Metallic. H = 6 - 6.5. Streak: dark gray. Color silvery gray to black; opaque; forms octahedrons; tarnishes gray. No cleavage; Attracted to a magnet and can be magnetized.
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Malachite
Formula:
Luster: NM
Hardness: 3.5-4
Streak: Green
Specific Gravity: 3.6-4.0
Properties/Cleavage: Opaque green. Forms laminations, coatings or masses. No cleavage. Effervesces with HCI.
Mineral Class: Carbonate
Uses: Gemstone, Ore of copper.
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Opal
NM. H = 5 - 5.5. Streak: white. Colorless to white, orange, yellow, brown, blue, gray, green, or red; may have play of colors (opalescence); cleavage absent. Conchoidal fracture.
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Rhodonite
Composition: Manganese silicate, sometimes with some calcium, iron, and magnesium
Color: Red, pink, orange-red, and brownish-red. Massive specimens often have black veins running through them. Some Rhodonite specimens tarnish black or brown upon exposure to air.
Streak: colorless
Hardness: 5.5-6
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Silver
a soft white precious univalent metallic element having the highest electrical and thermal conductivity of any metal
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Sodalite
hardness:5.5-6
spec. gravity:2.14-2.4
streak:colorless
color:many esp. blue
group:silicates
crystal system: cubic
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Topaz
This mineral and gemstone is the birthstone for the month of November. It is a silicate mineral of aluminum and fluorine, and comes in a variety of colors, from blue to straw yellow. Name this, with a rank of 8 on the Mohs Scale.
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Tremolite
hardness: 5-6
specific gravity: 2.9-3.2
streak:whute
color:many esp. white
group:silicates
crys. system:monoclinic
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Ulexite
Almost always white, and looks like a densely-packed bundle of white threads. It's opaque in one direction, and conducts light in the other. It's fiber-optic abilities gave it the nickname "T.V. rock".
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