Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Category
Browse mineral and metamorphic rock specimens identified by the Rock Identifier community.
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Biotite Mica
Biotite, K(Mg,Fe)3AlSi3O10(F,OH)2
Yellow Quartzite (Beach Pebble)
Quartzite (primarily SiO2)
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Blue Quartzite
Quartzite (specifically a variety enriched with blue-coloring minerals)
Lapis Lazuli
Complex silicate rock containing lazurite, calcite, and pyrite
Wishing Rock (Quartz Vein in Host Rock)
Silicon dioxide (SiO2) vein in various host rocks
Quartzite Pebble (with Iron Inclusions)
Quartzite (primarily SiO2 with Fe2O3/FeOOH impurities)
Prasiolite (Green Quartz)
Silicon Dioxide (SiO2) with iron impurities
Diamond (Cut Gemstone)
Carbon (C)
Unakite (polished/tumbled)
Unakite, a hydrothermally altered granite composed mainly of epidote, pink potassium feldspar (orthoclase/microcline), and quartz
Rhodonite
Manganese Silicate (Mn, Fe, Mg, Ca)SiO3
Black Marble
Recrystallized Carbonate Rock (CaCO3)
Unakite
Epidote–K-feldspar–quartz granitoid (often called unakite)
Yellow Quartzite (River Pebble)
Quartzite (primarily SiO2)
Jasper and Greenstone Pebble
Siliceous rock / Metamorphic pebble
Agate
Silicon Dioxide (Chalcedony), SiO2
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartzite
Quartzite (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Agate
Silicon Dioxide (Chalcedony), SiO2
Glacial granite/granitoid boulder
Granite to granodiorite; chiefly quartz, feldspar, and biotite/hornblende
Magnetite (Lodestone variety)
Magnetite (Fe3O4)
Greenstone
Metabasalt (composed of chlorite, epidote, and actinolite)
Schist
Mica Schist
Fuchsite in Quartz
K(Al,Cr)2(AlSi3O10)(OH)2 in SiO2
Muscovite Mica Schist
Metamorphic rock rich in muscovite mica (KAl2(AlSi3O10)(F,OH)2)
Quartz
Quartz (SiO₂)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO₂)
White calcite (likely tumbled calcite or marble fragment)
Calcite, calcium carbonate (CaCO₃); if the specimen is granular and rock-like, it may be marble, a calcite-rich metamorphic rock
River Pebble (Sandstone / Quartzite)
Sedimentary rock (Quartz arenite / Quartzite pebble)
Smoky Quartz
Silicon Dioxide (SiO2)
Quartzite
Quartzite (SiO2)
Sedimentary Rock (Limestone or Siltstone pebble)
Sedimentary rock fragment
Quartzite River Rock
Quartzite (primarily SiO2)
Yellow Sapphire
Corundum (Al2O3)
Granite fragment
Felsic intrusive igneous rock; mainly quartz, alkali feldspar, plagioclase, and minor biotite/hornblende
Milky Quartz
Silicon Dioxide (SiO2)