Gneiss
Gneiss (High-grade regional metamorphic rock)
Category
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
Gneiss
Gneiss (High-grade regional metamorphic rock)
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Jasper with Agate Inclusions
Silicon Dioxide (SiO2) - variety of Quartz/Chert
Yellow Quartzite Pebble
Quartzite (primarily Silicon Dioxide - SiO2)
Clear Quartz
Silicon dioxide (SiO2)
Pyrite
Iron Disulfide (FeS2)
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Granite Glacial Erratic
Intrusive Phaneritic Felsic Rock (Granite)
Quartz (in a rock matrix)
Quartz (SiO2)
Vesicular Basalt
Vesicular Basalt (rich in silicate minerals mostly Plagioclase and Pyroxene)
Sandstone
Arenite (SiO2 based with quartz grains)
African Turquoise
African Turquoise (a trade name for Jasper, a variety of Chalcedony: SiO2)
Granite
Granite (composed primarily of Quartz, Feldspar, and Mica)
Quartzite Pebble (with Iron Inclusions)
Quartzite (primarily SiO2 with Fe2O3/FeOOH impurities)
Botryoidal Goethite
Goethite (α-Fe3+O(OH))
Pink Granite
Phaneritic Acidic Plutonic Rock (primarily K-feldspar, quartz, and plagioclase)
Dalmatian Stone (Dalmation Jasper)
Aplite with Arfvedsonite inclusions
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
Sandstone (Quartzose Sandstone)
Arenite (SiO2)
Turquoise (set in silver jewelry)
Turquoise - CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)
Sandstone (Quartzose)
Arenite (SiO2 based)
Sandstone
Arenite (composed primarily of SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Sandstone (specifically Red Sandstone)
Arenite (SiO2 with Iron Oxide)
Quartz Pebble (with probable inclusions or staining)
Quartz (Silicon Dioxide - SiO2)
Agate (Common Chalcedony)
Silicon Dioxide (SiO2)
Sandstone (with manganese staining)
Clastic sedimentary rock (primarily SiO2)
Basalt with Amygdules
Amygdaloidal Basalt
Basalt with Quartz Veins
Basalt (SiO2 range 45-52%)
Garnet
Almandine formula: Fe3Al2(SiO4)3
Agate
Agate (Cryptocrystalline Variety of Quartz, SiO2)
Sandstone
Arenite (Clastic Sedimentary Rock)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Herkimer Diamond
Quartz (Silica - SiO2)
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)
Fluorite (Rainbow Fluorite)
Calcium Fluoride (CaF2)
Porphyritic Basalt (with Quartz or Calcite inclusion)
Porphyritic Basalt (Matrix: SiO2/MgO/FeO, Phenocryst: likely Quartz or Calcite)
Vuggy Quartz on Matrix
Silicon Dioxide (SiO2)
Basalt
Basalt (Mafic volcanic rock)
Green Quartzite
Quartzite (primarily SiO2 with chlorite inclusions)