Mineral In Metamorphic Rock

Eclogite

Eclogite (Omphacite + Pyrope)

Slate

Metamorphic pelitic rock

Quartz with Host Rock

Silicon Dioxide (SiO2)

Quartz geode or quartz-bearing rock

Quartz (SiO₂), likely in a chalcedony- or basalt-hosted cavity

Banded Gneiss

Banded Gneiss (Metamorphic Rock)

Gneiss

Gneiss (High-grade metamorphic rock)

Weathered quartz-rich metamorphic rock

Likely quartzite or quartz-mica schist; predominantly SiO₂ quartz with possible feldspar and mica

Mica-rich metamorphic rock, probably phyllite or schist

Quartz–mica phyllite/schist, dominated by muscovite or biotite mica and quartz

Quartz-rich metamorphic rock, possibly mica schist

Muscovite–biotite schist with quartz; exact identification requires testing

Weathered quartz-rich metamorphic rock, likely quartzite

Quartzite (mostly SiO₂), possibly micaceous quartzite or quartz-rich schist

Quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly quartz (SiO₂), with minor iron-oxide and mica impurities

Quartz-rich metamorphic rock (likely quartzite)

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

Weathered gray metamorphic rock, likely slate or phyllite

Foliated metapelite; composition commonly quartz, mica, and chlorite

Uncertain gray metamorphic rock, likely gneiss or schist

Quartz–feldspar–mica rock; exact identification requires close examination

Gneiss

Gneissic Metamorphic Rock (Mineral composition: Quartz, Feldspar, Amphibole/Biotite)

Likely rough garnet-bearing metamorphic rock

Garnet schist or garnet amphibolite; reddish areas may be almandine garnet (Fe₃Al₂Si₃O₁₂)

Quartz-veined Granite or Gneiss Pebble

Silicate-rich metamorphic rock fragment

Grey Agate (Tumbled)

Silicon Dioxide (SiO2)

Garnetiferous Pegmatite

Pegmatite with Almandine Garnet and Muscovite

White quartz pebble (probable)

Quartz, silicon dioxide (SiO₂)

Tumbled quartz-rich pebble, possibly milky quartz or quartzite

Quartz (SiO₂), potentially quartzite if metamorphically recrystallized

Banded gneiss

Gneiss, likely biotite–quartz–feldspar gneiss

Biotite Schist

Biotite Schist (Metamorphic Rock featuring K(Mg,Fe)3AlSi3O10(OH)2)

Likely weathered gneiss

Foliated metamorphic rock, commonly quartz–feldspar–mica gneiss

Banded amphibolite (hornblende-rich metamorphic rock)

Amphibolite; predominantly hornblende ± plagioclase, with possible biotite and quartz

Pyrite

Iron Disulfide (FeS2)

Serpentine-rich metamorphic rock

Serpentinite, likely antigorite/lizardite with accessory magnetite or chromite

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartzite

Metamorphic Quartz Rock (SiO2)

Gneiss (Pebble)

Gneiss

Yellow Calcite

Calcium Carbonate (CaCO3)

Veined Pebble (Quartz/Calcite Veined Metamorphic/Sedimentary Rock)

Quartz / Calcite Veined Fault Breccia or Metamorphic Pebble

Pyrite (on Quartz/Host Rock)

Iron Sulfide (FeS₂)

Blue-gray metamorphic rock, likely slate or phyllite

Slate/phyllite; chiefly quartz, muscovite/illite, chlorite, and minor feldspar

Magnetite

Magnetite (Fe3O4)

Quartz with Chlorite inclusions

SiO2 with (Mg,Fe)3(Si,Al)4O10(OH)2⋅(Mg,Fe)3(OH)6

Epidote

Epidote (Ca2(Al, Fe)3(SiO4)3(OH))

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Garnet

Almandine-Pyrope group, X3Y2(SiO4)3

Gneiss

Metamorphic Gneiss

Felsic Drill Core (likely Gneiss or Granite)

Felsic Metamorphic Rock (Gneissic profile)