Quartz
Silicon Dioxide (SiO2)
mineral
Category
Sedimentary Or Metamorphic (Low Grade)
Browse sedimentary or metamorphic (low grade) specimens identified by the Rock Identifier community.
Learn about Sedimentary Or Metamorphic (Low Grade) in the encyclopedia
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Coal (most likely Bituminous or Anthracite)
Bituminous Coal (Grade of Coal), Anthracite (Grade of Coal)
Sedimentary Rock
Gneiss
Metamorphic rock (Gneiss)
metamorphic
Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Banded Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Tumbled pale greenish stone, likely serpentine or altered limestone
Probable serpentine-group rock (antigorite/lizardite), possibly serpentinite; identification is visual only
metamorphic
Garnet Schist
Garnet-bearing Mica Schist
metamorphic
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Gneiss (specifically Pink Gneiss)
Gneiss (high-grade regional metamorphic rock)
metamorphic
Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
River Cobble (Quartzite or Gneiss)
Metamorphic crystalline rock (predominantly SiO2 based)
metamorphic
Precious Opal
Hydrated silica (SiO2·nH2O)
mineraloid
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
mineral
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Coal (Anthracite or Bituminous)
Carbo caulis / Sedimentary Carbon
sedimentary
Aventurine (Green Quartz)
Silicon dioxide with inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
mineral
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Black Sapphire
Corundum (Al2O3)
mineral
Gneiss
Gneiss (high-grade metamorphic rock typically composed of quartz, feldspar, and mica)
metamorphic
Garnet (Almandine)
Almandine Garnet (Fe3Al2(SiO4)3)
Mineral
Potassium Feldspar (Microcline / Orthoclase)
KAlSi3O8
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Weathered banded metamorphic rock, likely gneiss
Banded gneiss; commonly quartz–feldspar–mica assemblage
metamorphic
Greenschist
Greenschist (Chlorite Schist)
metamorphic
Decorative polished pebbles
Likely mixed quartz-rich lithologies, including quartzite, jasper, and/or basalt
mineral
Orange Calcite
Calcite (CaCO3)
Mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Banded gneiss pebble
Biotite–quartz–feldspar gneiss (composition variable)
metamorphic
Gneiss
Banded Gneiss
metamorphic
Gneiss
Gneiss
metamorphic
Gneiss
Gneiss
metamorphic