Citrine
SiO2 (Silicon Dioxide)
Category
Browse organic gemstone specimens identified by the Rock Identifier community.
Citrine
SiO2 (Silicon Dioxide)
Variscite in Matrix
Variscite (AlPO4 · 2H2O)
Tektite (Indochinite)
Tektite (High-silica natural glass)
Citrine
Silicon Dioxide (SiO2)
Sunstone
Plagioclase Feldspar (Na,Ca)(Al,Si)4O8
Septarian Nodule
Septarian Concretion
Chert (White/Light Tan)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (specifically Tan/Brown Chert)
Chert (SiO2)
Quartz (Milky/Rose variety)
Silicon Dioxide (SiO2)
Olivine (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4
Amethyst (Druzy Quartz)
Amethyst (Silicon Dioxide - SiO2 with iron impurities)
Turquoise (Dyed Howlite or Magnesite imitation)
Hydrated phosphate of copper and aluminum / CuAl6(PO4)4(OH)8·4H2O
Peridot (Gem-quality Olivine)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
Turquoise in Matrix
Hydrous phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Red Garnet (likely Almandine)
Almandine (Fe3Al2(SiO4)3)
Peridot
Olivine ((Mg, Fe)2SiO4)
Sunstone
Plagioclase Feldspar (Na,Ca)(Al,Si)4O8
Turquoise
CuAl6(PO4)4(OH)8·4H2O
Healer's Gold (Pyrite and Magnetite in Schist)
Magnetite (Fe3O4) and Pyrite (FeS2) in Mica Schist
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
Amazonite
Potassium Feldspar (KAlSi3O8)
Quartz Geode
Silicon Dioxide (SiO2)
Septarian Nodule
Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)
Jasper
Jasper (Silicon Dioxide, SiO2)
Banded Chert (Jasper)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Green Jasper (with Quartz veining)
Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2
Banded Chert
Microcrystalline Quartz (SiO2)
Jasper (likely Brown or Brecciated)
Jasper (Silicon Dioxide, SiO2)
Peridot
Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4
Diamond (appearing in jewelry)
Diamond (pure Carbon, C)
Diamond (or Cubic Zirconia)
Carbon (C) or Zirconium Dioxide (ZrO2)
Pearl
Calcium carbonate (CaCO3) - mainly Aragonite with Conchiolin
Peach Moonstone
Orthoclase Feldspar (KAlSi3O8) with inclusions
Emerald with Matrix (Emerald in Mica Schist)
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Amethyst
Quartz (Silicon Dioxide with Iron impurities), SiO2