Alabaster
Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)
Category
Browse mineral_rock specimens identified by the Rock Identifier community.
Alabaster
Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Epidosite (Epidote-rich rock)
Epidosite (consisting primarily of Epidote: {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
Petrified Wood
Silicified Wood (SiO2)
Galena in Quartz Matrix
Lead Sulfide (PbS) in Silicon Dioxide (SiO2)
Sandstone (Pebble)
Arenite (SiO2 based)
Quartz Geode
Silicon Dioxide (SiO2)
Druzy Quartz on Limestone
Silicon Dioxide (SiO2) on Calcium Carbonate (CaCO3)
Fossilized Shark Tooth (Otodus)
Otodus sp. (calcium phosphate/hydroxylellite)
Calamites
Calamites (Pith cast fossil)
Orthoclase Feldspar
Potassium Aluminum Silicate (KAlSi3O8)
River Pebble (likely Quartzite or Chert)
Sedimentary Clast (Silicon Dioxide dominant)
Gneiss (with Quartz-Feldspar vein)
Gneiss (high-grade metamorphic rock) containing Quartz (SiO2) and Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Mixed mineral and rock collection
Predominantly quartz varieties, including amethyst, plus likely calcite, feldspar, mica, and miscellaneous polished stones
Yellow Chalcedony / Carnelian
Silicon Dioxide (SiO2)
Citrine
Silicon Dioxide (SiO2)
Tumbled milky quartz
Quartz (silicon dioxide, SiO₂)
Quartz Pebble
Silicon Dioxide (SiO2)
Vesicular basalt (likely weathered volcanic rock)
Basalt, commonly composed of plagioclase, pyroxene, and olivine
Quartz
Silicon Dioxide (SiO2)
Conglomerate
Clastic Sedimentary Rock
Sandstone
Arenite (primarily SiO2)
Yellow Quartz
Silicon Dioxide (SiO2)
Amazonite
Microcline (KAlSi3O8) with lead impurities
Green Aventurine
SiO2
Milky Quartz/Yellow Quartz
Silicon Dioxide (SiO2)
Chert / Flint
Cryptocrystalline quartz (SiO2)
Dark-colored Igneous Rock (likely Basalt or Diabase)
Basalt (extrusive igneous) or Diabase (intrusive igneous)
Quartz Pebble (with Iron Inclusions)
Silicon Dioxide (SiO2)
Granite River Rock
Intrusive igneous rock (composed mainly of quartz, alkali feldspar, and plagioclase)
Iron-rich weathered rock, likely limonite/goethite-bearing laterite
Limonite (variable hydrated iron oxides; chiefly goethite, α-FeO(OH))
Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Pink Himalayan Salt Rock
Halite (NaCl with trace iron oxide minerals)
Rough turquoise-bearing rock (probable turquoise matrix)
Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O, likely in a host-rock matrix
Iron-stained quartz-rich rock, possibly jasper or chert
Microcrystalline quartz (SiO₂) with iron oxides/hydroxides
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
Quartz Mineral
Silicon dioxide (SiO2)
Granite
Phaneritic Acidic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
Magnetite
Magnetite (Fe3O4)