Tumbled Stones (various)
Mixed Silica-based Minerals (primarily Quartz and Chalcedony)
mineral
Category
Mineral (Evaporite)
Browse mineral (evaporite) specimens identified by the Rock Identifier community.
Pearl
Calcium carbonate (CaCO3) + organic conchiolin (Biogenic Mineral)
mineral
Rose Quartz
Silicon Dioxide (SiO2) with inclusions of Dumortierite or similar minerals
mineral
Dumortierite Quartz
Al7BO3(SiO4)3O3 (Borosilicate mineral/Quartz inclusion)
mineral
Tiger's Eye
Tiger's Eye (SiO2 with crocidolite inclusions)
mineral
Amygdaloidal Rhyolite
Amygdaloidal felsic extrusive rock
igneous
Quartzite
Quartzite (Primary mineral: Quartz, SiO2)
metamorphic
Quartzite (River Cobble)
Quartzite (dominant mineral: Quatrz, SiO2)
metamorphic
Sandstone
Arenite (SiO2 based with mineral cement)
sedimentary
River Pebble (Brecciated Chert/Siltstone)
Silicon Dioxide (SiO2) with mineral inclusions
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
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock with secondary mineral fillings)
igneous
Sandstone (Quartz-rich)
Arenite (SiO2 based clastic rock)
sedimentary
Schist
Mica Schist
metamorphic
Schist (with Iron Oxide)
Mica Schist
metamorphic
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Vesicular Basalt
Vesicular Basalt (rich in silicate minerals mostly Plagioclase and Pyroxene)
igneous
Epidote in Matrix (likely Amphibolite or Gneiss)
Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)) in Metamorphic Matrix
metamorphic
Pegmatite (with smoky quartz and tourmaline/biotite)
Pegmatitic Granite
igneous
Sandstone
Arenite (primarily SiO2)
sedimentary
Man-made Slag (Industrial Byproduct)
Anthropogenic Glassy Residue
not a natural rock
Cinnabar
Mercury(II) sulfide (HgS)
mineral
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
igneous
Quartzite with inclusions
Metamorphic Rock (Mainly SiO2)
metamorphic
Marble
Metamorphosed Limestone (main mineral: Calcite, CaCO3)
metamorphic
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Calamites (Fossil)
Calamites sp. (Tracheophyta, Equisetopsida)
sedimentary
Granite Pegmatite with Tourmaline and Muscovite
Pegmatite (Feldspar: KAlSi3O8, Quartz: SiO2, Schorl: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH))
igneous
Sandstone
Arenite
sedimentary
Quartzite with inclusions
Metamorphosed Quartz-rich Rock (SiO2)
metamorphic
Manganese Oxide Crust on Limestone
Manganese Oxides (e.g., Pyrolusite MnO2 or Romanechite) on CaCO3
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
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
sedimentary (matrix) / mineral (inclusion)
Gneiss (specifically Micaceous Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
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
Magnetite
Iron(II,III) oxide (Fe3O4)
mineral
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)
mineral