Mineral In Metamorphic Rock

Foliated metamorphic rock, likely garnet-mica schist

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

Pale-green schist fragment

Chlorite–sericite schist, possibly containing epidote or actinolite

Quartzite

Metamorphic rock predominantly composed of Quartz (SiO2)

Quartzite

Metamorphic Quartzite (SiO2)

Green Slate or Metamorphic Rock with Moss/Lichen

Metamorphic rock / Phyllite or Slate variant

Quartz vein in foliated metamorphic rock

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

Slate

Slate (foliated metamorphic rock)

Green Aventurine (Tumbled)

Silicon Dioxide with Fuchsite Inclusion (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)

Quartzite (or Engineered Quartz Stone)

SiO2 (Silicon Dioxide)

Mica Schist

Mica Schist (Quartz-Mica Metamorphic Rock)

Garnet-bearing Schist / Conglomerate Specimen

Metamorphic rock with almandine garnet porphyroblasts

Pyrite-bearing metamorphic rock (probable pyrite schist)

Schist containing pyrite (FeS₂), with probable quartz and mica

Weathered metamorphic rock, likely greenschist or amphibolite

Chlorite–actinolite schist/amphibolite; composition likely quartz, feldspar, chlorite, amphibole, and epidote

Foliated metamorphic rock, likely biotite schist

Mica schist, chiefly quartz, feldspar, and biotite mica

Likely slate or fine-grained metamorphic rock

Slate; predominantly microscopic mica, quartz, and clay-derived minerals

Quartzite

Metamorphic rock predominantly composed of Quartz (SiO2)

Green Aventurine

Silicon Dioxide (Quartz with Fuchsite inclusions) - SiO2

Green Aventurine

Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2

Rounded metamorphic cobble, likely gneiss or amphibolite

Banding-free biotite–quartz–feldspar gneiss or amphibolite; exact identification requires testing

Quartz-rich metamorphic rock, likely quartzite or quartz-veined schist

Quartz (SiO₂) with mica/chlorite-rich schistose matrix; possibly minor feldspar and sulfides

Quartz-bearing metamorphic rock, possibly epidote/quartzite

Quartz-rich rock with possible epidote and feldspar; exact identification requires testing

Biotite-bearing metamorphic rock, possibly schist or gneiss

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

Amphibolite

Amphibolite

Dark gray veined metamorphic rock

Likely marble or quartzite; exact identification requires hardness and acid tests

Likely hornblende amphibolite fragment

Amphibolite, chiefly hornblende and plagioclase feldspar

Likely gray quartzite or quartz-rich metamorphic fragment

Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with mica or feldspar

Mica Schist with Vein

Mica Schist

Mica Schist with Biotite or Muscovite

Metamorphic rock rich in sheet silicates

Graphite-bearing metamorphic rock, likely graphitic schist

Graphitic schist; chiefly quartz, mica, feldspar, and graphite (C)

Likely micaceous metamorphic rock fragment

Probable phyllite or mica schist; quartz–muscovite-rich assemblage

Greenschist (or Serpentinite) with Quartz-Feldspar Vein

Metabasalt / Greenschist Facies Rock

Quartz-bearing altered rock

Likely quartz vein in weathered schist or gneiss; quartz is SiO₂

Garnet-bearing metamorphic rock

Likely garnet schist or garnet amphibolite; garnet is commonly almandine, Fe₃Al₂(SiO₄)₃

Pyrite-bearing metamorphic rock (probable schist or quartzite)

Quartz–mica schist with disseminated pyrite; approximate composition SiO₂ + phyllosilicates + FeS₂

Likely weathered metamorphic rock (quartzite or schist)

Quartz-rich foliated metamorphic rock; exact identification requires testing

Epidote

Epidote ({Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))

Weathered metamorphic rock, likely chlorite schist or greenstone

Chlorite-rich schist/greenschist; exact identification requires testing

Garnet (Almandine)

Almandine, Fe3Al2(SiO4)3

Dark metamorphic pebble, likely slate or phyllite

Slate/phyllite; chiefly fine-grained mica and quartz, with possible chlorite and graphite

White marble (likely calcitic marble)

Calcite-rich marble; primarily calcium carbonate, CaCO₃

Schist

Mica Schist (Medium-grade metamorphic rock)

Greenschist (Greenstone)

Greenschist (Metamorphic rock containing chlorite, actinolite, and epidote)