Galena

is a metallic. Very dense, gray, shiny, sulfide mineral. PbS

Magnetite

Leaves a black streak, metallic group, oxide mineral, Fe3O4 (is magnetic)

Graphite

Gray streak, blackish gray, metallic group, native element (you can write with it) C

Hematite

red and black, leaves a red streak, metallic group, oxide mineral. Fe203

Pyrite

black with gold, metallic group, black streak, fools gold, sulfide mineral FeS2

Garnet

Silicate mineral, Dark, red, glassy, non-metallic group, brittle Fe, Mg, Ca, Al

Halite

Salty Taste, not very dense, clear in color, cubic cleavage, halite mineral NaCl

Gypsum

scratch with fingernail, non-metallic, light, sulfate mineral, soft, CaS04 2H20

Calcite

Reacts with HCL, white, brown, clear, perfect cleavage, no 90 angles, carbonate mineral CaCO3

Fluorite

Purples, blues, yellow, clear, non-metallic, Illinois state mineral, soft, cleavage, halide mineral CaF2

Olivine

Silicate mineral, always olive green, isolated tetrahedral, no cleavage, hard, non-metallic group MgFe

Biotite Mica

dark mica, silicate, cleaves into thin sheets, non-metallic group, KMgFeAl,

muscovite mica

light mica, silicate, breaks into thin sheets, cleavage, soft, non-metallic group, Al

K Feldspar

pink and salmon colored, planes at 90, milky, silicate, non-metallic group, K Al

Quartz

SiO2, silicate mineral, non-metallic group, pink, purple, brown, clear, breaks into sharp edges, crystals, no cleavage, hard

Granite

phaneritic, silicic, felsic, light colored, Quartz. K-feldspar

Rhyolite

crystals not visible, (aphanitic or porphyritic) silicic, felsic, light colored, quarts, K-feldspar

Diorite

Intermediate, gray, phaneritic, K-feldspar, plagioclase feldspar, Biotite, quartz, augite

Andesite

Intermediate, gray, porphyritic, or aphanitic, K-feldspar, plagioclase feldspar, biotite, quartz

Gabbro

Mafic, dark brown or black, phaneritic, Ca-plagioclase, Olivine,

Basalt

Mafic, dark brown or black, Porphyritic or aphanitic, Ca-plagioclase, Olivine

Obsidian

Solid Glass, no crystals present

Pumice

Vernacular Glass, gray to tan

Conglomerate

Clastic , coarse grained, rounded clasts,

Breccia

Coarse grained, angular clasts

Quartz Sandstone

Medium grained, mostly quartz

Arkosic Sandstone

Medium grained, feldspar, Quartz,

Graywacke

Dirty sandstone, medium grained, quartz, rock fragments,

Shale

Very fine grained, very fine grained, clay minerals, and sometimes quartz

Coal

swamp environments, decomposed plant material, black often shiny, organic carbon

Coquina

calcite

Rock Salt

Halite

Chert

SiO2

Gneiss

alternating light and dark bands
light bands: quartz and feldspar
Dark bands: hornblende, augite, garnet, biotite, etc.

Schist

Sheet-like grains; scaly, "shitose" texture. Sparkly or shiny appearance. ("Shiny Schist")
minerals: biotite, muscovite, chlorite. Minor amounts of quartz, or dark silicate minerals

Phyllite

microscopic flakes of mica create a sheen (slight reflective surface)

Slate

parallel orientation of of mica flakes created "slatey cleavage" planes of weakness

Quartzite

very hard (scratches glass). visible grains of quartz