Rough Dark Green Sapphire
Corundum (Al2O3)
Category
Browse metamorphic rock (composed of multiple minerals) specimens identified by the Rock Identifier community.
Rough Dark Green Sapphire
Corundum (Al2O3)
Orthoclase Feldspar (Salmon variety)
Orthoclase, KAlSi3O8
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Granite
Granite
Greenstone
Greenschist (primarily composed of chlorite, actinolite, and epidote)
Slate
Slate (a fine-grained, foliated metamorphic rock). Mineral composition: Primarily composed of mica minerals (muscovite, chlorite, sericite) and quartz, with minor amounts of hematite, pyrite, and other accessory minerals.
Arkosic Sandstone
Arkose
Quartz
Silicon Dioxide (SiO2)
Slate with Red Sandstone Landscaping Rock
Foliated Pelitic Metamorphic Rock (Slate) and Ferruginous Sandstone
Epidote
Epidote - Ca2(Al,Fe)3(SiO4)3(OH)
Black Sand (Magnetite Sand)
Magnetite (Fe3O4)
Granite
Phaneritic Felsic Intrusive Igneous Rock
Limestone
Calcium Carbonate (CaCO3)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
Granite Pebble (River Rock)
Granite (composed primarily of Quartz, Feldspar, and Mica)
Schist
Mica Schist
Mica Schist
Mica Schist (Predominantly Muscovite/Biotite)
Quartzite River Rock (with Limonite staining)
Quartzite (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone (Yellow/Tan)
Clastic sedimentary rock (primarily SiO2 with iron oxide staining)
Sandstone (with potential Arkose/Lithic characteristics)
Arenite (Sedimentary rock composed of sand-sized grains)
Banded Gneiss (Variety of Gneiss)
Gneiss (specifically, a variety exhibiting prominent banding; mineral composition can vary, but often contains quartz, feldspar, mica, and amphibole)
Schist
Mica Schist (formula variable based on mineral content, typically containing [K,Al,Fe,Mg,Si,O,H])
Sandstone
Arenite (primarily SiO2)
Sandstone (with cross-bedding)
Arenite (composed primarily of Quartz: SiO2)
Quartzite
Quartzite (SiO2)
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
Coquina / Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate - CaCO3)
Sandstone (Pebble/Conglomerate fragment)
Sandstone (clastic sedimentary rock)
Quartz (likely Jasper or Chert variety)
Quartz (SiO₂)
Unakite (or Epidote-rich Granite)
Unakite (composed of Epidote {Ca2(Al, Fe)3(SiO4)3(OH)}, Pink Orthoclase Feldspar {KAlSi3O8}, and Quartz {SiO2})
Dalmatian Jasper (Dalmatian Stone)
Peralkaline rhyolite
Serpentinite
Serpentinite (complex silicate minerals including Lizardite, Antigorite, and Chrysotile)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 cement)
Sandstone
Clastic Sedimentary Rock (composed mostly of SiO2)
Basalt
Mafic Volcanic Rock (composed of plagioclase, pyroxene, and olivine)
Seraphinite (Clinochlore)
Clinochlore (Mg,Fe2+)5Al(Si3Al)O10(OH)8
Schist
N/A (a rock type, not a mineral formula)
Sandstone
Clastic Sedimentary Rock (composed primarily of Quartz, SiO2)
Puddingstone
Conglomerate
Rhyolite
Rhyolite (High-silica volcanic rock)
Dacite
Dacite (Intermediate volcanic rock)