Metamorphic (Likely Gneiss Or Schist Based On Texture)

Gneiss

Banded orthogneiss or paragneiss, typically quartz–feldspar–mica bearing

Biotite (Mica)

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

Foliated metamorphic rock, likely schist or gneiss

Quartz–feldspar–mica schist/gneiss; exact identification requires a fresh surface and tests

Biotite in Host Matrix

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

Weathered gneiss

Foliated gneiss, chiefly quartz–feldspar–mica

Muscovite

Muscovite (KAl2(AlSi3O10)(OH)2)

Mica Schist

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

Gneiss

Gneiss (Metamorphic Rock)

Biotite-bearing gneiss or schist

Quartz–feldspar–biotite metamorphic rock

Muscovite Mica

Muscovite, KAl2(AlSi3O10)(OH)2

Hornblende-bearing metamorphic rock (likely amphibolite)

Amphibolite, chiefly hornblende amphibole and plagioclase feldspar

Gneiss

Gneiss

Biotite (Mica)

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

Dark schist or gneiss cobble

Foliated metamorphic rock, likely biotite–quartz–feldspar schist/gneiss

Mica Schist with Vein

Mica Schist

Schist

Mica Schist (primarily consisting of muscovite KAl2(AlSi3O10)(OH)2 or biotite K(Mg,Fe)3(AlSi3O10)(OH)2)

Mica (Biotite or Phlogopite Buchsam)

Silicate Mineral (Phyllosilicate family)

Gneiss Pebble

Gneiss (Metamorphic Foliated Rock)

Muscovite Mica

Muscovite [KAl2(AlSi3O10)(OH)2]

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(F,OH)2)

Gneiss

Gneiss

Foliated metamorphic rock, likely gneiss or schist

Biotite–quartz–feldspar gneiss/schist; exact identification requires mineral and texture testing

Biotite Gneiss

Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)

Green Kyanite

Kyanite (Al2SiO5)

Garnet (likely Almandine or Pyrope)

Garnet (Group Name), Fe3Al2(SiO4)3 or Mg3Al2(SiO4)3

Fuchsite

Chromian Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)

Red Garnet

Pyrope or Almandine (X3Y2(SiO4)3)

Foliated metamorphic rock, likely garnet-mica schist

Mica schist, probably muscovite/biotite schist with small garnet or quartz inclusions

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gneiss

Gneiss

River Stone (likely Quartzite or Limestone)

Silicon dioxide (SiO2) or Calcium carbonate (CaCO3)

Weathered metamorphic rock, likely mica schist or gneiss

Quartz–feldspar–mica schist/gneiss; exact identification is uncertain from the photograph

Biotite-bearing metamorphic rock, possibly schist or gneiss

Mica schist/gneiss; chiefly quartz (SiO₂), feldspar, and biotite mica

Dark mafic metamorphic rock, likely amphibolite

Amphibolite; chiefly hornblende amphibole and plagioclase feldspar

Schist

Mica Schist (primarily Muscovite and Quartz)

Gneiss (Pebble)

Gneiss

Likely mica-rich metamorphic rock (schist)

Muscovite–biotite schist; composition commonly quartz + feldspar + mica

Garnet (Almandine/Pyrope series)

Garnet Group - X3Y2(SiO4)3

Tumbled quartz-rich pebble

Milky quartz with possible feldspar or mica inclusions (SiO₂-dominant)

Biotite (Black Mica)

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

Schist

Mica Schist

Banded gneiss

Gneiss, commonly quartz–feldspar–biotite gneiss