Metamorphic (Likely Gneiss Or Schist Based On Texture)

Gneiss

High-grade metamorphic rock (Gneiss)

Waterworn greenstone pebble

Likely serpentinite or chlorite-rich metamorphic rock; exact identification requires testing

Pyrite Schist

Metamorphic rock containing FeS2 (Pyrite) with mica and quartz

Kyanite (Purple variety)

Kyanite (Al₂SiO₅)

Gneiss

Metamorphic Gneiss (High-grade regional metamorphism)

Greenschist

Greenschist (Chlorite Schist)

Sandstone (Quartz-rich)

Sandstone (SiO2 dominated)

Greenschist (Chlorite Schist)

Greenschist (containing Chlorite, Actinolite, and Epidote)

Mica Schist

Crystalline Schist (often primarily Muscovite or Biotite sheet silicates)

Schist (Diamond Drill Core)

Mica Schist

Gneiss

Gneiss

Gneiss

Gneiss (High-grade Metamorphic Rock)

Greenschist

Chlorite schist

Schist

Mica Schist (Quartz-Muscovite-Biotite Schist)

Mica Schist

Mica Schist (primarily composed of Muscovite/Biotite)

Quartz-rich metamorphic rock, likely mica schist

Mica schist; chiefly quartz (SiO₂) with biotite/muscovite mica and possible feldspar

Fuchsite

Chrome-bearing Muscovite [K(Al,Cr)2(AlSi3O10)(OH)2]

Coarse-grained granite or granitic gneiss

Granite; primarily quartz (SiO₂), feldspar, and mica/amphibole

Mica Schist

Mica Schist (primarily Muscovite and/or Biotite Schist)

Gneiss

High-grade foliated metamorphic rock

Almandine Garnet (weathered)

Almandine (Fe3Al2(SiO4)3)

Garnet-bearing metamorphic rock, likely mica schist

Biotite–garnet schist; commonly includes quartz, feldspar, biotite, and almandine garnet

Muscovite Mica Schist

Muscovite Schist (KAl2(AlSi3O10)(OH)2)

Mica Schist

Mica Schist

Chlorite (Small Flakes/Sand)

Chlorite Group (Magnesium Iron Aluminum Silicate Hydroxide - (Mg,Fe)3(Si,Al)4O10(OH)2·(Mg,Fe)3(OH)6)

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Schist

N/A (a rock type, not a mineral formula)

Fuchsite or Green Mica Schist

Muscovite variant (KAl2(AlSi3O10)(OH)2 with Cr)

Feldspar (likely Orthoclase or Plagioclase)

Tectosilicate Feldspar (KAlSi3O8 to (Ca,Na)(Al,Si)4O8)

Garnet Schist

Almandine-Mica Schist

Granite Gneiss River Rock

Gneiss

River Pebble (Gneiss or Quartzite variant)

Metamorphic rock specimen (likely Quartzite or Gneiss)

Schist (Biotite Schist)

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

Amphibolite / Biotite Schist

Amphibolite (rich in Hornblende and Plagioclase feldspar)

Gneiss (Metamorphic Rock Pebble)

Foliated Metamorphic Rock (Quartz-Feldspar Gneiss / Granitic Gneiss)

Gneiss

Foliated quartzo-feldspathic gneiss, commonly containing biotite or amphibole

Almandine Garnet

Almandine, Fe3Al2(SiO4)3

Rough Garnet in Matrix

Almandine Garnet (Fe3Al2Si3O12)

Biotite Schist

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

Schist (Micaceous Schist)

Schist (containing mainly Muscovite and Quartz)

Banded Gneiss

Gneiss (High-grade metamorphic rock)