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48 terms

Mineral and Rock Identification

Mineral Igeneous Sedimentary Metamorphic
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Calcite
MINERAL
Color: Colorless/White
Hardness: 3
Cleavage: 3 directions not @ 90
ID: Reacts with HCl
Quartz
MINERAL
Color: Colorless, PInk, Purple, Gray, Green, Yellow
Hardness: 7
Cleavage: Conchoidal
ID: six-sided crystals, very hard, granular-ish, glassy luster
Na-Plagio Feldspar
MINERAL
Color: Light, Milky
Hardness: 6
Cleavage: 2 directions at 90
ID: striations, white color
Biotite
MINERAL
Color: Black/Brown
Hardness: 2.5-3
Cleavage: perfect in 1 direction
ID: can be peeled in sheets, dark colored mica, resinous luster
Muscovite
MINERAL
Color: translucent tan
Hardness: 2-2.5
Cleavage: perfect in 1 direction
ID: can be peeled in sheets, light colored mica, pearly luster
Magnetite
MINERAL (Metallic)
Color: iron black
Hardness: 6
Cleavage: rarely seen
ID: Strongly magnetic, deep black
Ca-Plagio Feldspar
MINERAL
Color: Dark Grey/Blue, Milky
Hardness: 6-6.5
Cleavage: 2 directions, near 90
ID: striations, dark color, sometimes a blue sheen
Gypsum
MINERAL
Color: Colorless, White
Hardness: 2
Cleavage: perfect in one direction
ID: generally flatter than Halite/Calcite, can scratch with fingernail
Halite
MINERAL
Color: Colorless, White
Hardness: 2.5
Cleavage: 3 directions at 90 (cuboidal)
ID: cuboidal, tastes like salt, glassy luster
Augite
MINERAL
Color: Dark Green
Hardness: 5-6
Cleavage: 2 directions at almost 90
ID: dark green color (pyroxene), prismatic crystals, single chain silicate (Dark Pyroxene)
Hornblende
MINERAL
Color: Black/Dark Green
Hardness: 5-6
Cleavage: two directions at 56 and 124
ID: blackish-green (Dark Amphibole)
Pyrite
MINERAL (Metallic)
Color: Brassy Gold
Hardness: 5-6.5
Cleavage: Concoidal/Uneven
ID: black streak, gold color
Galena
MINERAL (Metallic)
Color: Lead Gray
Hardness: 2.5
Cleavage: three directions at 90
ID: very heavy, gray streak, cuboidal, lead composition
K-Feldspar
MINERAL
Color: Peachy Salmon
Hardness: 6-6.5
Cleavage: 2 cleavages at 90
ID: color, striations
Graphite
MINERAL (Metallic)
Color: dark gray
Hardness: 1
Cleavage: perfect in 1 direction
ID: writes on paper, super light, scratch with fingernail, greasy feel, made entirely of Carbon
Hematite
MINERAL (Metallic)
Color: black, red, sparkly slate-blue
Hardness: 5.5-6.5
Cleavage: rare
ID: red streak, slightly magnetic, rust common, shimmer
Olivine
MINERAL
Color: Green
Hardness: 6.5-7
Cleavage: conchoidal
ID: green color, quartz-like granular pattern, light yellow streak
Sphalerite
MINERAL
Color: Brown, Yellow, Black
Hardness: 3.5
Cleavage: 6 directions
ID: resinous luster, streak smells like rotten eggs
Granite
IGNEOUS
Texture: Coarse
Minerals Present: K-Feldspar, Amphibole, Quartz
Cooling History: Slow (crystals develop)
Composition: Felsic
Tectonic Setting: Continental
ID: K-Feldspar/Amphibole blend
Gabbro
IGNEOUS
Texture: Coarse
Minerals Present: Plagioclase Feldspars, Pyroxene
Cooling History: Slow (plagio crystals evident)
Composition: Mafic
Tectonic Setting: Continental
ID: Granular crystals in a mafic matrix
Scoria
IGNEOUS
Texture: Porous/Vesicular
Minerals Present: pyroxenes, micas, andesite, too fine
Cooling HIstory: Rapid Cooling with release of gases
Composition: Mafic
Tectonic Setting: Ocean Hotspot
ID: vesicles, reddish-brown color
Porphyritic Andesite
IGNEOUS
Texture: Porphyritic
Minerals Present: olivines, amphiboles
Cooling History: Slow then quick cooling, to get the large crystals surrounded by fine matrix
Composition: Intermediate (darker)
Tectonic Setting: Ocean-Continent Convergent Boundary/Volcanic island arcs
ID: large grains in fine matrix and darker than rhyolite
Porphyritic Rhyolite
IGNEOUS
Texture: Porphyritic
Minerals Present: quartz, k-feldspars
Cooling History: Slow then quick cooling, to get the large crystals surrounded by fine matrix
Composition: Felsic (lighter)
Tectonic Setting: Continent-Continent Collision Zone
ID: large grains in fine matrix and lighter than andesite
Basalt
IGNEOUS
Texture: Fine-Grained
Minerals Visible: fine-grained mafic minerals
Cooling History: very quick cooling (fine)
Composition: Mafic
Tectonic Setting: Ocean Floor/Hot Spot
ID: dark, heavy, fine-grained, smooth
Obsidian
IGNEOUS
Texture: Glassy
Minerals Visible: None
Cooling History: Instant
Composition: mafic-intermediate
Tectonic Setting: continental
ID: glassy black, concoidal fractures
Peridotite
IGNEOUS
Texture: Coarse
Minerals Visible: olivine, pyroxene
Cooling History: Slow
Composition: Ultra-Mafic
Tectonic Setting: Continent Collision zones
ID: super dark green with high specific gravity and coarse grains
Diorite
IGNEOUS
Texture: Coarse
Minerals Visible: muscovite, plagios
Cooling History: Slow
Composition: Intermediate
Tectonic Setting: Continental
ID: Salt and pepper color
Pumice
IGNEOUS
Texture: porous (aphanitic)
Minerals Visible: feldspars, quartz, muscovites
Cooling History: Quick cooling of frothy/gassy felsic lava
Composition: Felsic
Tectonic Setting: Continental Hot Spots
ID: super light, porous, light color
Volcanic Breccia
IGNEOUS
Texture: pyroclastic
Minerals: k-feld matirx, chunks of plagio/muscovite
Cooling History: sudden explosion of ash and rock
Composition: felsic
Tectonic Setting: continental hot spot
ID: super chunky
Vesicular Basalt
IGNEOUS
Texture: porous
Cooling History: Quick Cooling
Composition: Mafic/Intermediate
Tectonic Setting: ocean hotspot
ID: dark mafic with vesicles
Conglomerate
SEDIMENTARY
Texture: rounded pebbles, coarse-grained
Components: Clastic
Transporting Agent: rounded sediment weathered before deposition
Environment: river deposition, alluvial fan
Fossiliferous Limestone
SEDIMENTARY
Texture: fine-grained matrix, abundant fossils
Components: Biogenic
Transporting Agent: River Current
Environment: shallow marine
Other: Fossils + reacts with HCL
Sandstone
SEDIMENTARY
Texture: fine, glittery, sandpaper feel
Components: Clastic
Transporting Agent: wind, river current
Environment: Desert Dunes or Beach
Other: can be brown/gray/tan/red in color, grittier than shale and siltstone
Shale
SEDIMENTARY
Texture: fine-grained mud, forms sheets
Components: clastic
Transporting Agent: gravity/current
Environment: Deep Marine (bottom mud)
Other: can be black, grey, tan, brown, red
Breccia
SEDIMENTARY
Texture: angular pebbles in fine matrix (only difference between conglomerate)
Components: Clastic
Transporting Agent: A sudden collision so that the angular bits stick together
Environment: Meteor Impact/Glacier
Siltstone
SEDIMENTARY
Texture: super-fine-grained, gritty
Components: Clastic
Transporting Agent: current
Environment: Muddy/Silty Marine
Micritic Limestone
SEDIMENTARY
Texture: super-fine-grained, smooth
Components: Biogenic
Transporting Agent: lithification of lime mud
Environment: marine (tiny dead sea-life bits)
Other: reacts with HCL
Coquina
SEDIMENTARY
Texture: super-coarse, made of shells
Components: Biogenic
Transporting Agent: shells and sand bonding quickly (poorly sorted)
Environment: marine environment then buried
Other: Reacts with HCL
Arkose
SEDIMENTARY
Texture: coarse, angular grains, feldspar chunks
Components: Clastic
Transporting Agent: sediment deposited close to source (poorly sorted), and feldspar isn't given enough time to weather down
Environment: alluvial fan
Other: red color, chunky
Coal
SEDIMENTARY
Texture: fine-grained, greasy, blocky shape
Components: Biogenic
Transporting Agent: time, gravity
Environment: layers in swamp
Other: resinous luster, smell
Chert
SEDIMENTARY
Texture: super-fine-grained, smooth/glassy, conchoidal fractures
Components: Chemical
Transporting Agent: precipitated from a water/quartz solution
Other: does not react with HCL, lighter color
Phyllite
METAMORPHIC
Composition: Aluminious (Chlorite, Clay)
Texture: fine-grained, silky sheen, foliated sheets
Type of Meta: Regional
Grade: Medium
Mica Schist
METAMORPHIC
Composition: Aluminious (Biotite, Muscovite)
Texture: coarse-grained, horizontal alignment, foliation of mica sheets
Type: Regional
Grade: High
Slate
METAMORPHIC
Composition: Mafic
Texture: Fine-grained foliation, aligned clay flakes, dull texture, dark black, smooth
Type: Regional
Grade: Low
Gneiss
METAMORPHIC
Composition: quartzo-feldspathic, mafic, or calcareous
Texture: Foliated and layered, segregated into light and dark bands (characteristic)
Type: Regional/ Dynamothermal
Grade: High
Marble
METAMORPHIC
Composition: Calcareous
Texture: Granoblastic, Coarse
Type: Contact/Burial in non-differential stress environment
Grade: low-medium
Other: reacts with HCL, generally white/pink for our purposes
Garnet Schist
METAMORPHIC
Composition: Aluminious (Biotite, Muscovite, Garnet)
Texture: coarse-grained, horizontal alignment, foliation of mica sheets, different from other schists they have garnets
Type: Regional
Grade: Medium-High
Quartzite
METAMORPHIC
Composition: quartzo-feldspathic
Texture: granoblastic, coarse
Type: Contact/BUrial in non-differential stress environment
Grade: Can't determine in a quartz/feldspar