Amethyst
Silicon Dioxide (SiO2) with iron impurities
Category
Browse mineral and organic gemstone specimens identified by the Rock Identifier community.
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Amethyst/Smoky Quartz Cluster
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Dalmatian Stone (commonly Dyed)
Dalmatian Jasper (Peralkaline igneous rock)
Prasiolite and Quartz Crystal Cluster
Quartz (SiO2); Prasiolite is a variety of Quartz
Amber
Fossilized tree resin (not a true mineral as it is organic and amorphous); Chemical formula is highly variable, but often approximated as C10H16O.
Milky Quartz
Silicon Dioxide (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
Garnet (likely Almandine or Pyrope)
Garnet Group (e.g., Almandine: Fe3Al2(SiO4)3; Pyrope: Mg3Al2(SiO4)3)
Herkimer Diamond
Quartz (Silicon Dioxide) - SiO2
Quartz
Silicon Dioxide (SiO2)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Quartz in Host Rock
Silicon Dioxide (SiO2) in Rhyolite or Granite matrix
Fuchsite (Green Muscovite in Quartz)
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Milky Quartz
Silicon Dioxide (SiO2)
Spinel
Magnesium Aluminum Oxide (MgAl2O4)
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)
Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Amethyst (in jewelry)
Silicon Dioxide (SiO2) with iron impurities
Pegmatite
Granitic Pegmatite
Rutilated Quartz
Silicon Dioxide (SiO2) with Titanium Dioxide (TiO2) inclusions
Amethyst Geode
Amethyst (Silicon Dioxide, SiO2)
Granitic Pegmatite
Granite Pegmatite (coarse-grained intrusive igneous rock)
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
Peridot
Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Nuummite
Nuummite (Orthorhombic amphiboles: Anthophyllite and Gedrite)
Fluorite
Calcium Fluoride (CaF2)
Carnelian
SiO2 (Silicon Dioxide), a variety of Chalcedony
Aventurine (likely Green Aventurine)
Silicon Dioxide (SiO2) with mineral inclusions
Orange Calcite
Calcium Carbonate (CaCO3)
Olivine in Basalt (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4 (Mineral) within Basalt (Rock)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Moonstone (Feldspar variety)
Orthoclase Feldspar (KAlSi3O8)
Quartz / Milky Quartz
Silicon Dioxide (SiO2)
Ruby (Raw/Rough)
Corundum (Al2O3 with Chromium trace)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with Iron Oxide inclusions)
Falcon's Eye (Blue Tiger's Eye)
Pseudomorph of Quartz after Crocidolite (SiO2)
Obsidian
Volcanic glass (Mainly SiO2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)