Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
Category
Browse sedimentary or metamorphic (base substrate) specimens identified by the Rock Identifier community.
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Gneiss (Banded Gneiss)
Gneiss
Greenschist
Greenschist facies rock (containing chlorite, actinolite, albite, and epidote)
Gneiss
Gneiss (High-grade metamorphic rock)
Granite Gneiss
Gneiss (High-grade metamorphic rock)
Gneiss
Gneiss (High-grade metamorphic rock)
Gneiss
Gneiss (high-grade metamorphic rock)
Graywacke (River Cobble)
Graywacke (Lithic Sandstone)
Chert (variously Flint or Jasper gravel)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Coquina
Bioclastic Limestone
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
Chert (and Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Marble
Recrystallized Calcite (CaCO3)
Garnet Schist
Almandine Garnet-bearing Mica Schist
Pyrite
Iron Disulfide (FeS2)
Garnet Schist or Garnet-bearing Quartzite
Metamorphic rock containing Almandine Garnet (Fe3Al2(SiO4)3) and Quartz (SiO2)
Greenstone (Greywacke or Nephrite Jade variant)
Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)
Garnet (likely Almandine)
Almandine Garnet, Fe3Al2(SiO4)3
Yellow Jasper
Chalcedony (SiO2) with iron oxide inclusions
Wallboard/Drywall (Gypsum-based)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Chert (and Chert-based Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Conglomerate
Clastic sedimentary rock (Polymictic Conglomerate)
Green Fluorite
Calcium Fluoride (CaF2)
Gneiss with Quartz/Feldspar Vein
Quartz-Feldspathic Gneiss
Banded Gneiss
Gneiss (High-grade metamorphic rock)
Gneiss
Gneiss (High-grade metamorphic rock)
Limestone
CaCO3 (principally composed of Calcite)
River Pebble (Likely Chert or Fine-Grained Sandstone/Quartzite)
Siliciclastic clast (likely Chert or Quartzarenite/Quartzite pebble)
Garnet (Almandine)
Almandine, Fe3Al2(SiO4)3
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2
Magnetite
Magnetite (Fe3O4)
Anthracite Coal
Anthracite (Carbon-rich metamorphic sedimentary rock)
Quartzite Pebble
Quartzite (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Concrete
Anthropogenic Sedimentary Conglomerate (Cement mixture: typically Ca2SiO4, Ca3SiO5, Ca3Al2O6)
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
Banded Gneiss with Quartz Vein
Foliated Metamorphic Rock (Gneiss)
Quartz
Silicon Dioxide (SiO2)
Jasper (Green)
Silicon dioxide (SiO2)