Granite
Granite
Category
Browse mineral (tectosilicate) specimens identified by the Rock Identifier community.
Granite
Granite
Granite
Phaneritic Plutonic Felsic Rock
Sandstone
Sandstone (arenite is a more specific geological term for a clean sandstone, while wacke refers to a dirty sandstone with significant matrix)
Tumbled Stones (various)
Mixed Silica-based Minerals (primarily Quartz and Chalcedony)
Pearl
Calcium carbonate (CaCO3) + organic conchiolin (Biogenic Mineral)
Ocean Jasper
Silicon Dioxide (SiO2) with iron and other mineral inclusions
Rose Quartz
Silicon Dioxide (SiO2) with inclusions of Dumortierite or similar minerals
Dumortierite Quartz
Al7BO3(SiO4)3O3 (Borosilicate mineral/Quartz inclusion)
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium), CuAl6(PO4)4(OH)8·4H2O
Red Sandstone
Arenite (Ferruginous Sandstone)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Greenschist
Greenschist (Chlorite-Albite-Epidote Schist)
Sandstone (likely Arkosic or Lithic Sandstone)
Clastic Sedimentary Rock (SiO2 with assorted minerals)
Greenschist
Greenschist (Chlorite Schist facies)
Granite
Phaneritic plutonic rock (primarily Quartz, Feldspar, and Mica)
Shale
Shale (clay-sized silicate minerals)
Desert Rose (Baryte or Selenite variant)
Barium Sulfate (BaSO4) or Gypsum (CaSO4·2H2O) with Sand inclusions
Garden Quartz
Included Quartz (SiO2 with accessory minerals such as Chlorite, Hematite, or Feldspar)
Amethyst Sage Agate
Silicon Dioxide (SiO2) with trace minerals (Manganese/Iron oxides)
Ruby
Corundum (mineral species), variety: Ruby (Al2O3 with Cr3+ as the chromophore)
Bismuth
Bismuth (Bi)
Fossilized Shark Tooth
Fossilised Chondrichthyes dental specimen (likely Otodus or Carcharias sp.)
Tiger's Eye
Tiger's Eye (SiO2 with crocidolite inclusions)
Quartz on Feldspar
Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)
Barite
Barium Sulfate (BaSO4)
Geode (unopened)
SiO2 - Chert-shelled concretion (mostly Quartz)
Granite Pegmatite with Tourmaline and Muscovite
Pegmatite (Feldspar: KAlSi3O8, Quartz: SiO2, Schorl: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH))
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Calamites (Fossil)
Calamites sp. (Tracheophyta, Equisetopsida)
Sandstone
Arenite
Quartzite with inclusions
Metamorphosed Quartz-rich Rock (SiO2)
Fossilized Shark Tooth (Sand Tiger)
Carcharias taurus (fossil specimen)
Lapis Lazuli
Lapis lazuli (a rock primarily composed of Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
Note regarding image quality
Manganese Oxide Crust on Limestone
Manganese Oxides (e.g., Pyrolusite MnO2 or Romanechite) on CaCO3
Goethite
Goethite (FeO(OH))
Amethyst
Quartz (Silicon Dioxide with iron impurities), SiO2
Amazonite
K(AlSi3O8) - Potassium Aluminum Silicate (variety of Microcline)
Petrified Wood
Silicified Wood (SiO2)
Black Opal
Hydrated Amorphous Silica (SiO2 "n" H2O)