Olivine in Basalt (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4 in Vesicular Basalt
Category
Browse rock specimens identified by the Rock Identifier community.
Olivine in Basalt (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4 in Vesicular Basalt
Turquoise (set in silver jewelry)
Turquoise - CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)
Turquoise in Matrix
Hydrous phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Jasper (Iron-stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Glauconitic Sandstone
Glauconitic arenite (contains (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Turquoise
CuAl6(PO4)4(OH)8·4H2O
Carnelian Agate
Carnelian (SiO2 with iron oxide impurities)
Petrified Wood
Silicified Wood (SiO2)
Chert (Flint)
Microcrystalline quartz (SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Quartz / Quartzite
Quartzite (primarily Silicon Dioxide, SiO2)
Banded Gneiss
Gneiss (Metamorphic high-grade rock)
Chert (specifically Jasper/Brown Chert)
Silicon Dioxide (SiO2)
Granite
Intrusive Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Quartzite
Quartzite (primarily SiO2)
Quartzite Pebble
Quartzite (primarily SiO2)
Sandstone concretion (Ironstone-stained)
Arenite with Limonite/Hematite staining (Silica-based with Iron Oxides)
Quartzite
Quartzite (SiO2)
Pink Quartzite
Quartzite (primarily SiO2 with trace Fe2O3)
Quartzite
Quartzite (primarily SiO2)
Pink Granite
Felsic Plutonic Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)
Basalt
Mafic igneous rock (primarily Plagioclase feldspar and Pyroxene)
Quartzite
Quartzite (primarily SiO2)
Pumice
Pumice (Vesicular Rhyolite/Dacite)
Travertine
Calcareous Tufa (CaCO3)
Basalt
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Greenstone / Serpentinite
Serpentinite (composed primarily of minerals from the serpentine group Mg3Si2O5(OH)4)
Quartz Druzy on Agate (River Cobble)
Silicon Dioxide (SiO2)
Basalt with vesicles (Amygdaloidal Basalt)
Amygdaloidal Basalt (predominantly Plagioclase and Pyroxene)
Quartzite (Iron-stained)
Quartzite (SiO2)
Pumice
Vesicular volcanic glass (primarily SiO2)
Quartzite
Quartzite (primarily SiO2)
Sandstone (likely Ferruginous)
Arenite (SiO2 based with Fe2O3/FeO(OH) cement)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Basalt (with Plagioclase Phenocrysts)
Porphyritic Basalt
Porphyritic Andesite
Andesite (Porphyry)
Pumice (likely weathered/water-worn)
Vesicular volcanic glass
Garnet Schist
Almandine Garnet-Mica Schist (X₃Y₂(SiO₄)₃)
Chert (Jasper variety)
Silicon Dioxide (SiO2)