Gneiss
Banded Metamorphic Rock (Gneiss)
Category
Browse sedimentary or metamorphic (low grade) specimens identified by the Rock Identifier community.
Gneiss
Banded Metamorphic Rock (Gneiss)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Agate
Silicon Dioxide (Chalcedony), SiO2
Granitic Gneiss Pebble
Gneiss (felsic metamorphic rock)
Pink chalcedony (likely rough agate/chalcedony)
Microcrystalline quartz, SiO₂; chalcedony variety, possibly iron-bearing
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Marble
Recrystallized Calcite (CaCO3)
Granite Gneiss
Gneiss (High-grade regional metamorphic rock)
Optical Calcite
Calcium Carbonate (CaCO3)
Oyster shell fragment
Ostreidae shell; primarily calcite (CaCO₃)
Quartz
Silicon Dioxide (SiO2)
Jasper
Silicon dioxide (SiO2)
Rounded basalt cobble
Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase and pyroxene, commonly with minor olivine and iron oxides
Dumortierite in Quartz
Dumortierite (Al6O3(BO3)(SiO4)3) with Quartz (SiO2)
Likely biotite-bearing metamorphic rock (schist or gneiss)
Mica schist/gneiss; chiefly quartz, feldspar, and biotite mica
Garnet (Almandine/Pyrope variety)
Silicate mineral group; typically Fe3Al2(SiO4)3 (Almandine) or Mg3Al2(SiO4)3 (Pyrope)
Calcite
Calcite (Calcium Carbonate, CaCO3)
Venetian Gold Granite
Phaneritic Felsic Igneous Rock (Granite)
Amethyst
Quartz (Silicon Dioxide, SiO2)
Greenschist
Greenschist (Chlorite-Epidote-Actinolite Schist)
Greenschist
Greenschist facies rock (containing chlorite, actinolite, albite, and epidote)
Graphite
Graphite (Native Carbon, C)
Jade
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Banded gneiss pebble
Gneiss, typically quartz–feldspar–mica banded rock
Gneiss (Gneissic Granite Pebble)
Metamorphic rock rich in Quartz, Feldspar, and Mica
Gneiss (with Quartz and Mica)
Gneiss
Gneiss (Stream-worn Cobble)
Gneiss (Metamorphic rock composed primarily of Quartz, Feldspar, and Mica)
Banded Gneiss
Gneiss (Metamorphic rock of variable mineralogy, often quartz-feldspar base)
River Stone (Granitic Gneiss)
Foliated Granitic Gneiss
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Dumortierite Quartz
Dumortierite-bearing Quartz (Al7BO3(SiO4)3O3)
Green Calcite
Calcium Carbonate (CaCO3)
Quartz / Feldspar Specimen
SiO2 (Quartz) / KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8 (Feldspar Group)