Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
Category
Browse metamorphic rock (specifically a rock composed of minerals) specimens identified by the Rock Identifier community.
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Gold Ore in Matrix
Native Gold (Au) in Quartz/Host Rock
Basalt
Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Sandstone (with Limonite staining)
Arenite (primarily SiO2 with FeO(OH)·nH2O)
Basalt with Mineral Vein (Cobble)
Basalt (with likely Quartz/Calcite vein)
Quartz Pebble
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Granite
Phaneritic Felsic Igneous Rock (Main minerals: SiO2, KAlSi3O8, NaAlSi3O8)
Dragon Vein Agate
Chalcedony (Quartz) - SiO2
Calcite on Limestone (or Fossil)
Calcium Carbonate (CaCO3)
Quartzite
Metamorphic Quartzite (predominantly SiO2)
Quartzite Pebble
Quartzite (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Druzy)
Silicon Dioxide (SiO2)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Quartzite Pebbles
Quartzite (SiO2 silicon dioxide dominant)
Sandstone (lithic wacke)
Arenite / Lithic Wacke (mostly SiO2 with rock fragments)
Almandine Garnet
Iron aluminum silicate (Fe3Al2(SiO4)3)
Red Agate
Agate (Cryptocrystalline variety of Quartz, SiO2)
Yellow Quartzite
Quartzite (primarily SiO2)
Geode (unopened)
SiO2 - Chert-shelled concretion (mostly Quartz)
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Gold Nugget
Native Gold (Au)
Quartzite
Quartzite (composed primarily of SiO2)
Dragon Stone
Ohko Stone (Argillaceous sedimentary rock)
Red Sandstone
Ferruginous Sandstone (SiO2 dominated with Fe2O3 cement)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Matrix
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Quartzite
Quartzite (SiO2)
Quartzite
Quartzite (SiO2)
Basalt with Scoria/Vesicular Texture
Vesicular Basalt (Iron-rich/Oxidized)
Granite (weathered pebble)
Granite (plutonic igneous rock)
Amygdaloidal Basalt
Amygdaloidal Basalt (extrusive volcanic rock)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Turquoise
Hydrated copper and aluminum phosphate (CuAl6(PO4)4(OH)8·4H2O)
Druzy Quartz on Chalcedony Matrix
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Fossilized Horn Coral
Rugosa