Serpentinite
Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe)3Si2O5(OH)4)
Category
Browse mineral (man made composite) specimens identified by the Rock Identifier community.
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe)3Si2O5(OH)4)
Milky Quartz
Silicon Dioxide (SiO2)
Magnetite (Lodestone variety)
Magnetite (Iron(II,III) oxide, Fe3O4)
Granite
Granite (a plutonic igneous rock composed of quartz, feldspar, and mica)
Fluorite (likely)
Calcium Fluoride (CaF2)
Lapis Lazuli
Lapis Lazuli (a rock composed primarily of Lazurite (Na,Ca)₈[(S,Cl,SO₄,OH)₂|(Al₆Si₆O₂₄)], with varying amounts of Calcite, Pyrite, and Sodalite.)
Sandstone (Quartzose Pebble)
Clastic Sedimentary Rock (Litharenite/Quartz arenite)
Glauconitic Sandstone
Glauconitic Quartz Arenite
Sandstone (Red Sandstone)
Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide)
Serpentinite (Serpentine Rock)
Primarily composed of serpentine group minerals, such as antigorite, chrysotile, and lizardite. Chemical formula for serpentine minerals is (Mg,Fe)3Si2O5(OH)4.
Fossilized Shark Tooth
Carcharhinus sp. (likely Bull or Requiem shark family)
Banded Calcite (often sold as 'Mexican Onyx' or 'Calcite Onyx')
Calcite (Calcium Carbonate, CaCO3)
Stilbite
Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O)
Slate
Foliated Metamorphic Rock (composed mainly of clay minerals or micas)
Granite fragment
Granite (Felsic Plutonic Rock)
Calcite
Calcite (Calcium Carbonate, CaCO3)
Sandstone
Arenite (primarily SiO2)
Quartz Geode
Crystalline Silicon Dioxide (SiO2) in a Geode
Hematite
Iron(III) oxide (Fe2O3)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)
Garnet (Almandine/Pyrope series)
Silicate mineral (Almandine: Fe3Al2Si3O12; Pyrope: Mg3Al2Si3O12)
Hematite Pebble
Hematite (Alpha Fe2O3)
Cinnabar in Quartz
Silicon Dioxide (SiO2) with Mercury Sulfide (HgS) inclusions
Smoky Quartz with Feldspar
SiO2 (Quartz) with KAlSi3O8 (Potassium Feldspar)
Jasper
Silicon dioxide (Microcrystalline Quartz, SiO2)
Tiger's Eye
Fibrous Quartz (SiO2) with iron inclusions
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Quartz (Citrine variety)
Silicon Dioxide (SiO2)
Prehnite
Prehnite, Ca2Al2Si3O10(OH)2
Amazonite
Microcline (KAlSi3O8) with Pb impurities
Citrine
Silicon dioxide (SiO2)
Amethyst
Quartz (Silicon Dioxide with Iron impurities), SiO2
Amazonite
KAlSi3O8 (Potassium aluminum silicate - blue-green variety of Microcline)
Fire Opal (in Matrix)
Hydrated Silica (SiO2·nH2O)
Sunstone
Plagioclase Feldspar (Na,Ca)(Al,Si)4O8
Amazonite
Potassium Aluminum Silicate (KAlSi3O8)
Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
Quartz with mica and feldspar (Pegmatite fragment)
Granitic Pegmatite (composed mainly of SiO2 with KAlSi3O8)
Howlite
Howlite (Ca2B5SiO9(OH)5)
Red Sandstone
Arenite with iron oxide (Hematite) cement
Sandstone with Iron Oxide Staining
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)