Metamorphic Rock

Biotite-bearing metamorphic rock, possibly schist or gneiss

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

Likely foliated metamorphic rock, possibly schist

Mica schist or micaceous quartzite; exact identification is uncertain from the photograph

Rhodonite-bearing metamorphic rock

Manganese-rich metamorphic rock, chiefly rhodonite (MnSiO₃), with quartz and manganese oxides

Garnet amphibolite / Metamorphic Rock

Garnet Amphibolite (Hornblende - Almandine schist/gneiss)

Quartz-veined Metamorphic Rock

Quartz-veined Schist or Gneiss

Granite with Epidote

Granite, containing quartz, feldspar, and epidote

Chalcopyrite-bearing metamorphic rock (possibly bornite/chalcopyrite ore)

Likely quartz–sulfide rock containing chalcopyrite (CuFeS₂); identification from the image is tentative

Hornblende-bearing metamorphic rock (likely amphibolite)

Amphibolite, chiefly hornblende amphibole and plagioclase feldspar

Hornblende-bearing metamorphic rock (probable amphibolite)

Amphibolite; chiefly hornblende amphibole and plagioclase feldspar

Serpentine-bearing metamorphic rock (likely chromite/vesuvianite-bearing serpentinite)

Serpentinite, chiefly serpentine-group minerals [(Mg,Fe)₃Si₂O₅(OH)₄], with dark accessory minerals

Polished dark river pebble, likely serpentinite or altered ultramafic rock

Serpentinite (predominantly serpentine-group minerals; identification is provisional)

Granite or granitic pebble

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

Weathered green metamorphic rock, possibly serpentinite or greenstone

Likely serpentinite (serpentine-group minerals) or chlorite/epidote-rich greenschist; exact identification requires testing

Weathered metamorphic rock, likely greenschist or amphibolite

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

Serpentine-rich metamorphic rock

Serpentinite, likely with magnetite and weathered ultramafic minerals

Foliated metamorphic rock, likely biotite gneiss or schist

Biotite-rich gneiss/schist; chiefly quartz, feldspar, and biotite mica

Layered metamorphic rock, possibly banded gneiss

Gneiss (tentative; exact identification requires closer examination)

Foliated metamorphic rock, likely quartz-mica schist

Quartz–mica schist, commonly containing muscovite/biotite and quartz

Garnet-bearing metamorphic rock

Garnet amphibolite or garnet schist; almandine garnet (Fe₃Al₂Si₃O₁₂) likely

Weathered metamorphic rock, likely quartz-mica schist

Quartz–mica schist; composition typically quartz + muscovite/biotite ± feldspar

Coarse-grained gray metamorphic rock, likely gneiss

Biotite–quartz–feldspar gneiss (probable)

Likely weathered metamorphic rock (possibly schist or gneiss)

Indeterminate; probable mica-rich quartz–feldspar metamorphic rock

Weathered metamorphic rock, likely schist or gneiss

Quartz–feldspar–mica metamorphic rock; exact identification requires testing

Weathered granite or granitic gneiss

Granite; primarily quartz, feldspar, and mica

Fossil-bearing metamorphic rock, possibly schist with a fossil imprint

Micaceous schist; apparent fossil material is unidentified

Quartz-veined metamorphic rock, likely quartzite or schist

Quartz-rich metamorphic rock with a milky-quartz vein; exact host rock is indeterminate from the photo

Foliated metamorphic rock, likely garnet-mica schist

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

Weathered metamorphic rock, likely schist or slate

Foliated pelitic metamorphic rock; commonly muscovite–chlorite schist or phyllite

Pyrite-bearing metamorphic rock (probable schist or quartzite)

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

Likely mafic metamorphic rock with sulfide mineralization

Probable amphibolite or hornblende–biotite schist, locally bearing pyrite/other sulfides

Weathered metamorphic rock, likely chlorite schist or greenstone

Chlorite-rich schist/greenschist; exact identification requires testing

Garnet-bearing metamorphic rock, likely garnet schist or amphibolite

Almandine garnet (Fe₃Al₂Si₃O₁₂) in mica- or amphibole-rich matrix

Garnet-bearing metamorphic rock

Likely garnet schist or garnet-bearing mica schist; garnet is commonly almandine, Fe₃Al₂(SiO₄)₃

Weathered metamorphic rock, possibly schist or gneiss

Indeterminate; likely quartz–feldspar–mica rock, potentially greenschist or gneiss

Serpentine-rich metamorphic rock

Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and carbonates

Weathered schistose metamorphic rock

Likely mica schist or phyllitic schist; composition commonly quartz, muscovite/biotite, and feldspar

Serpentine-rich metamorphic rock

Serpentinite, likely antigorite/lizardite with magnetite and possible chlorite or talc

Graphite-bearing metamorphic rock, likely graphitic schist

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

Weathered metamorphic rock, likely schist or phyllite

Quartz–mica schist/phyllite (exact identification requires a fresh surface and tests)

Serpentine-rich metamorphic rock

Serpentinite, chiefly serpentine-group minerals (antigorite, lizardite, chrysotile) with possible magnetite, talc, and carbonate

Serpentine-rich metamorphic rock

Serpentinite, dominated by serpentine-group minerals (antigorite/lizardite/chrysotile), with possible magnetite and carbonate

Serpentine-rich metamorphic rock (probable serpentinite)

Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, or chrysotile), commonly with magnetite and chromite