Amethyst
Crystalline Quartz (SiO2 with iron impurities)
Category
Browse organic gemstone specimens identified by the Rock Identifier community.
Amethyst
Crystalline Quartz (SiO2 with iron impurities)
White Quartz
Silicon Dioxide (SiO2)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Eagle Eye / Grey Tiger Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Quartz (possibly Citrine or Smoky Quartz variety)
Silicon Dioxide (SiO2)
Quartz (Milky or Clear Quartz fragment)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Smoky Quartz
Quartz (Silicon Dioxide, SiO2)
Eudialyte with Syenite
Eudialyte: Na15Ca6Fe3Zr3Si(Si25O73)(O,OH,H2O)3(Cl,OH)2
Chrysocolla in Matrix
Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O
Amethyst (as seen in jewelry)
Silicon Dioxide (SiO2) with iron impurities
Amethyst Quartz
Amethyst (Silicon Dioxide, SiO2)
Quartz (Milky to Clear)
Silicon Dioxide (SiO2)
Moonstone
Orthoclase (KAlSi3O8) with inclusions of Albite (NaAlSi3O8)
Amazonite
K(AlSi3O8), Microcline
Apache Tears (Obsidian)
Hydrated Volcanic Glass (Amorphous SiO2 + H2O)
Sunstone (Feldspar)
Plagioclase Feldspar ((Ca, Na)(Al, Si)4O8)
Turquoise
Turquoise - CuAl6(PO4)4(OH)8·4H2O
Quartz in Host Rock
Silicon Dioxide (SiO2) in Rhyolite or Granite matrix
Pearl
Calcium Carbonate (Aragonite and Calcite), CaCO3
Carnelian
Carnelian Agate (Silica: SiO2)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
White Topaz
Aluminum Silicate Fluoride Hydroxide; Al2SiO4(F,OH)2
Graphite
Graphite (Carbon, C)
Pink Opal / Peruvian Opal
Hydrated amorphous silicon dioxide (SiO2·nH2O)
Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Feldspar
KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8
Turquoise
Hydrous phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Amazonite
Microcline (KAlSi3O8)
Mixed Gemstone Collection
SiO2 (Quartz varieties) and Biogenic CaCO3 (Nacre)
Carnelian
Chalcedony (Silicon Dioxide, SiO2 with Iron Oxide impurities)
Peridotite
Peridotite (Ultramafic Rock)
Lake Superior Agate
Cryptocrystalline Quartz (SiO2) with Iron impurities
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Peridot
Olivine (specific variety: gem-quality forsterite), (Mg,Fe)2SiO4
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with ferric iron impurities)
Carnelian Agate
Carnelian (Silicon Dioxide - SiO2 with Iron Oxide impurities)
Jasper Pebble
Silicon dioxide (SiO2) with iron oxide impurities