Amethyst
SiO2 (Silicon Dioxide with iron impurities)
Category
Browse gemstone specimens identified by the Rock Identifier community.
Amethyst
SiO2 (Silicon Dioxide with iron impurities)
Amethyst with Marcasite accents
Amethyst (Silicon Dioxide SiO2) and Marcasite (Iron Sulfide FeS2)
Hematite
Iron(III) oxide (Fe2O3)
Blue Quartzite
Silicon Dioxide (SiO2) with inclusions
Quartz (Milky or Rough Variety)
Silicon Dioxide (SiO2)
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Pietersite
Brecciated Crocidolite in Quartz (Chalcedony)
Citrine
Silicon Dioxide (SiO2) - Yellow Quartz variety
Peach Moonstone
Orthoclase (Potassium Aluminum Silicate), KAlSi3O8
Agate (specifically Oco or Banded Agate)
Agate (a variety of Chalcedony), SiO2 (Silicon Dioxide)
Olivine (Peridotite)
Olivine Group; (Mg, Fe)2SiO4
Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Yellow Quartz (Citrine Quartz Pebble)
Silicon Dioxide (SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Amazonite
Amazonite (KAlSi3O8); a green variety of Microcline feldspar
Unakite (Tumbled)
Epidotized Granite
Red Jasper
Jasper (Silicon Dioxide) - SiO2
Amethyst
SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities
Rough Citrine Quartz
Citrine (Silicon Dioxide, SiO2 with iron impurities)
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)
Moonstone (Adularia)
Potassium aluminum silicate (KAlSi3O8)
Turquoise, Pearl, and Coral Necklace
CuAl6(PO4)4(OH)8·4H2O (Turquoise) / CaCO3 (Pearl and Coral)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Freshwater Pearl
Aragonite / Biogenic Calcium Carbonate (CaCO3)
Garnet
Almandine (Fe3Al2(SiO4)3)
Quartz Geode (Cracked)
Silicon Dioxide (SiO2)
Yellow Jasper
Silicon Dioxide (SiO2) with iron hydroxides (Goethite/Limonite)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Green Jasper
Silicon Dioxide (SiO2) with iron silicate inclusions
Cullet Glass (Slag Glass)
Amorphous Silicon Dioxide (Industrial Byproduct)
Blue Goldstone
Aventurine Glass
Fuchsite
K(Al,Cr)2(AlSi3O10)(OH)2 (Chromium-rich Muscovite)
Jasper
Silicon Dioxide (SiO2)
Sunstone
Oligoclase (Plagioclase Feldspar) - (Na,Ca)(Si,Al)4O8 with Hematite or Copper inclusions
Green Jasper (Chert)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Blue Topaz (facetted in jewelry)
Aluminum silicate fluoride hydroxide (Al2SiO4(F,OH)2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Citrine Quartz
Crystalline Quartz (SiO2) with iron impurities
Yellow Chalcedony
Cryptocrystalline Quartz (SiO2)
Quartzite
Metamorphosed Sandstone (SiO2)