Biotite Schist
Biotite Schist
Category
Browse mineral (sedimentary context) specimens identified by the Rock Identifier community.
Biotite Schist
Biotite Schist
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Bauxite
AlOx(OH)3-2x (mixture of Gibbsite, Boehmite, and Diaspore)
Blue Kyanite
Kyanite (Al2SiO5)
Quartz (in a rock matrix)
Quartz (SiO2)
Fossilized Megalodon Tooth Fragment
Otodus megalodon (Carcharocles megalodon fossil)
Sandstone (Quartz-rich)
Arenite (primarily SiO2)
Sandstone (likely Quartz Sandstone)
Arenite (composed primarily of SiO2)
Sandstone (likely Quartzose Sandstone)
Arenite (primarily SiO2)
Quartz (Chert/Chunky Chalcedony)
Silicon Dioxide (SiO2)
Fluorite
Calcium Fluoride (CaF2)
Quartz Mineral
Silicon Dioxide (SiO2)
Potassium Feldspar and Quartz
KAlSi3O8 (Potassium Feldspar) and SiO2 (Quartz)
Carnelian and White Quartz Bracelet
Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Kyanite in Quartz
Kyanite (Al2SiO5) with Quartz (SiO2)
Banded Calcite (often sold as 'Mexican Onyx' or 'Calcite Onyx')
Calcite (Calcium Carbonate, CaCO3)
Sandstone
Arenite
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
Bauxite
Bauxite (Al2O3·2H2O)
Limonite Pseudomorph after Pyrite
Limonite (Hydrous iron oxides e.g., FeO(OH)·nH2O) pseudomorphing Pyrite (FeS2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Sandstone or Limestone
Arenite or Calcareous Sedimentary Rock
Sandstone
Arenite (primarily SiO2)
Blue Banded Agate (Dyed)
Silicon Dioxide (SiO2) - variety of Chalcedony
Galena
Lead Sulfide (PbS)
Native Sulfur
Sulfur (S)
Blue Calcite (commonly sold as Caribbean Calcite)
Calcium Carbonate (CaCO3)
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
Druzy Quartz Geode (Oco or Moroccan variety)
Silicon Dioxide (SiO2)
Satin Spar (Selenite)
Gypsum (CaSO4·2H2O)
Blue Calcite
Calcium Carbonate (CaCO3)
Quartz Druzy Geode
Silicon Dioxide (SiO2)
Pink Calcite (Mangano Calcite)
Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Hematite
Iron(III) oxide (Fe2O3)
Hematite
Iron(III) oxide (Fe2O3)
Biotite (Black Mica)
Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2
Blue Kyanite
Kyanite (Al2SiO5)
Jasper
Silicon Dioxide (SiO2)