Citrine (Heat-treated or Natural Quartz)
Silicon Dioxide (SiO2)
Category
Browse mineral and organic gemstone specimens identified by the Rock Identifier community.
Citrine (Heat-treated or Natural Quartz)
Silicon Dioxide (SiO2)
Citrine
Quartz (Silicon Dioxide - SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Amethyst
Amethyst (SiO2 with iron impurities)
Amazonite
K(AlSi3O8) - Microcline variant
Moldavite
Moldavite (Siliceous vitreous substance)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Amazonite
Potassium aluminum silicate (Microcline); KAlSi3O8
Amazonite (or Amazon Stone)
Potassium Feldspar (Microcline), K(AlSi3O8)
Clear Quartz
SiO2 (Silicon Dioxide)
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
Amazonite
Microcline (Amazonstone), K(AlSi3O8)
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Sandstone Chert Concretion
Silica-cemented Concretion (primarily SiO2)
Chert Pebble (Jasper/Quartz variety)
Microcrystalline Quartz (SiO2)
Mother of Pearl (Nacre)
Aragonite (layered with organic polymers), CaCO3
Purple Agate (Dyed Chalcedony)
SiO2 (Silicon Dioxide) with organic dyes
Epidote
Epidote ({Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))
Epidote
{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Red Jasper
Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Yellow Sapphire or Citrine
Al2O3 (Corundum) or SiO2 (Quartz)
Quartz Geode
Silicon Dioxide (SiO2) within a secondary sedimentary structure
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Quartz Geode in Chert/Limestone Matrix
Silicon Dioxide (SiO2) within Sedimentary Host Rock
Chert (Flint variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (and/or River Pebble)
Microcrystalline quartz (SiO2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Tahitian Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
Citrine
Silicon dioxide (SiO2) - yellow quartz variety
Aquamarine
Beryl (Be3Al2Si6O18 with trace Fe2+)
Petrified Wood
Silicified Wood (SiO2)
Tanzanite
Blue Zoisite (Ca2Al3(SiO4)(Si2O7)O(OH))
Petrified Wood
Silicified wood (principally Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Chert (often called Flint)
Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Blue Chalcedony
Silicon Dioxide (SiO2)