Metamorphic (Likely Gneiss Or Schist Based On Texture)

Weathered schist or foliated metamorphic rock

Mica-quartz schist, tentatively; mineral composition likely quartz, mica, and feldspar

Biotite (Black Mica) in Host Rock

K(Mg,Fe)3AlSi3O10(OH,F)2

Polished garnet bead bracelet

Garnet group, likely almandine–pyrope solid solution; commonly approximated as Fe₃Al₂(SiO₄)₃–Mg₃Al₂(SiO₄)₃

Muscovite Mica (on Quartz Matrix)

Muscovite - KAl2(AlSi3O10)(OH)2

Banded amphibolite (likely hornblende schist)

Amphibolite; chiefly hornblende ± actinolite and plagioclase feldspar

Graphite

Graphite (Carbon, C)

Biotite Mica

Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)

Gneiss (with Mica and Quartz)

Gneissic Metamorphic Rock

Lepidolite in Mica Schist

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2

Milky Quartz (with Iron Oxide staining)

Quartz (Silicon Dioxide - SiO2)

Blue Kyanite in Schist

Al2SiO5 in Mica Schist

Blue Sapphire

Corundum (Al2O3 with iron and titanium trace elements)

Blue-gray quartz-bearing metamorphic rock (likely gneiss or schist)

Quartz–feldspar–mica rock; exact identification requires testing

Unidentified dark, foliated metamorphic rock

Likely biotite schist or hornblende-bearing gneiss; exact identification requires testing

Biotite Schist

Biotite Gneissic Schist (K(Mg,Fe)3AlSi3O10(OH)2)

Muscovite (Mica) in Quartz Matrix

Muscovite (KAl2(AlSi3O10)(OH)2) and Quartz (SiO2)

Muscovite (White Mica)

Muscovite - Potassium aluminum silicate: KAl2(AlSi3O10)(F,OH)2

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Kyanite

Kyanite (Al₂SiO₅)

Schist

Mica Schist (Composition typically involves Muscovite, Biotite, Quartz, and Feldspar)

Weathered quartz-rich pebble

Likely quartz-bearing granite or granitic gneiss; exact identification requires testing

Graphite

Graphite (Native Carbon, C)

Mica Schist

Mica Schist (predominantly Muscovite or Biotite sheet silicates)

Quartz vein in weathered host rock

Quartz (SiO₂), likely in a weathered metamorphic or igneous matrix

Mica Schist

Mica Schist (varies based on mineral makeup, often Biotite/Muscovite schist)

Schist (Graphite or Mica rich)

Crystalline Schist (often containing Muscovite, Biotite, or Graphite)

Mica schist

Muscovite–biotite schist, composed mainly of mica and quartz

Mica Schist

Schist (muscovite-quartz dominant)

Likely garnet-bearing rock or almandine garnet fragment

Garnet group, probably almandine (Fe₃Al₂(SiO₄)₃)

Tumbled garnet (likely almandine)

Almandine garnet, iron-aluminum nesosilicate (Fe₃Al₂Si₃O₁₂)

Banded metamorphic rock, likely gneiss or schist

Foliated quartz–feldspar–mica rock; exact identification requires a closer view or mineral testing

Schist

Mica Schist

Likely graphite-rich schist

Graphitic schist; chiefly graphite and quartz/mica

Likely metamorphic schist or gneiss

Mica-rich quartz-feldspar schist/gneiss; exact identification requires testing

Pyrite-bearing Schist

Pyritic Quartz-Mica Schist with FeS2 inclusion

Mica (Muscovite)

Potassium aluminum silicate - KAl2(AlSi3O10)(OH)2

Quartz vein in foliated metamorphic rock

Likely quartz-bearing schist or gneiss; visible crystal is quartz (SiO₂)

Biotite Schist

Biotite Schist

Banded metamorphic rock, likely gneiss

Biotite–quartz–feldspar gneiss, possibly amphibolite-bearing

Dark, mica-rich metamorphic rock (probable schist or gneiss fragment)

Likely biotite–quartz–feldspar schist; exact identification requires testing

Granite Gneiss

Gneiss (high-grade metamorphic rock)

Schist

Schist (metamorphic rock)