Red Sandstone
Arenite (primarily composed of SiO2 with Fe2O3 cement)
sedimentary
Category
Mineral Group
Browse mineral group specimens identified by the Rock Identifier community.
Chrysocolla on Matrix
Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Tiger's Eye
Tiger's Eye (SiO2 with crocidolite inclusions)
mineral
Pearl
Calcium carbonate (CaCO3) + organic conchiolin (Biogenic Mineral)
mineral
Tumbled Stones (various)
Mixed Silica-based Minerals (primarily Quartz and Chalcedony)
mineral
Rose Quartz
Silicon Dioxide (SiO2) with inclusions of Dumortierite or similar minerals
mineral
Dumortierite Quartz
Al7BO3(SiO4)3O3 (Borosilicate mineral/Quartz inclusion)
mineral
Quartzite
Quartzite (Primary mineral: Quartz, SiO2)
metamorphic
Quartzite (River Cobble)
Quartzite (dominant mineral: Quatrz, SiO2)
metamorphic
River Pebble (Brecciated Chert/Siltstone)
Silicon Dioxide (SiO2) with mineral inclusions
sedimentary
Sandstone
Arenite (SiO2 based with mineral cement)
sedimentary
Black Jasper
Black Jasper (Silicate mineral - SiO2)
sedimentary
Goldstone
Not a natural mineral or rock. It is an ornamental glass.
Manufactured Glass (Simulant)
Quartzite
Quartzite (Primary mineral: Quartz, SiO2)
metamorphic
Chrysocolla
Hydrated copper phyllosilicate, Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)
mineral
Amygdaloidal Rhyolite
Amygdaloidal felsic extrusive rock
igneous
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock with secondary mineral fillings)
igneous
Vesicular Basalt
Vesicular Basalt (rich in silicate minerals mostly Plagioclase and Pyroxene)
igneous
Schist
Mica Schist
metamorphic
Sandstone (Quartz-rich)
Arenite (SiO2 based clastic rock)
sedimentary
Pegmatite (with smoky quartz and tourmaline/biotite)
Pegmatitic Granite
igneous
Epidote in Matrix (likely Amphibolite or Gneiss)
Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)) in Metamorphic Matrix
metamorphic
Man-made Slag (Industrial Byproduct)
Anthropogenic Glassy Residue
not a natural rock
Cinnabar
Mercury(II) sulfide (HgS)
mineral
Schist (with Iron Oxide)
Mica Schist
metamorphic
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
igneous
Marble
Metamorphosed Limestone (main mineral: Calcite, CaCO3)
metamorphic
Sandstone
Arenite (primarily SiO2)
sedimentary
Quartzite with inclusions
Metamorphic Rock (Mainly SiO2)
metamorphic
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Sandstone
Arenite
sedimentary
Granite Pegmatite with Tourmaline and Muscovite
Pegmatite (Feldspar: KAlSi3O8, Quartz: SiO2, Schorl: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH))
igneous
Calamites (Fossil)
Calamites sp. (Tracheophyta, Equisetopsida)
sedimentary
Lapis Lazuli
Lapis lazuli (a rock primarily composed of Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
metamorphic
Note regarding image quality
Indeterminate
Quartzite with inclusions
Metamorphosed Quartz-rich Rock (SiO2)
metamorphic
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
sedimentary (matrix) / mineral (inclusion)
Manganese Oxide Crust on Limestone
Manganese Oxides (e.g., Pyrolusite MnO2 or Romanechite) on CaCO3
sedimentary
Granite
Granite (a common name for a felsic intrusive igneous rock)
Igneous Rock
Ferrochrome Slag
Anthropogenic slag (Fe-Cr alloy waste)
industrial byproduct
Gneiss (with Mica and Quartz)
Gneissic Metamorphic Rock
metamorphic