Tiger's Eye
Silicon Dioxide (SiO2) with Limonite/Goethite pseudomorphs after Crocidolite
Category
Browse mineral and organic gemstone specimens identified by the Rock Identifier community.
Tiger's Eye
Silicon Dioxide (SiO2) with Limonite/Goethite pseudomorphs after Crocidolite
Blue Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of asbestiform silicates)
Red Beryl
Bixbite (Be3Al2Si6O18 with Mn3+ ions)
Amethyst
SiO2 (Silicon Dioxide with iron impurities)
Citrine
Silicon Dioxide (SiO2) - Yellow Quartz variety
Yellow Quartz (Citrine Quartz Pebble)
Silicon Dioxide (SiO2)
Peridot (Olivine)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Amazonite
Amazonite (KAlSi3O8); a green variety of Microcline feldspar
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)
Lapis Lazuli
Sodium aluminum silicate with sulfur (main component: Lazurite [(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2])
Black Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Quartz Geode
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Pearl (Imitation or Cultured)
Calcium Carbonate (Aragonite/Calcite) - CaCO3
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
Chert (Flint Nodules)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Raw Corundum (Sapphire/Ruby variant)
Aluminum oxide (Al2O3)
Arsenopyrite in Quartz Matrix
Arsenopyrite (FeAsS) with Quartz (SiO2)
Chert (varieties include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Hypersthene
(Mg,Fe)SiO3 - Enstatite-Ferrosilite series
Diamond (or Cubic Zirconia)
Carbon (C) or Zirconium Dioxide (ZrO2)
Talc
Talc (Mg₃Si₄O₁₀(OH)₂)
Yellow Chert (Jasper)
Microcrystalline Quartz (SiO2)
Dendritic Agate (or Dendritic Opal)
SiO2 (for Agate), SiO2·nH2O (for Opal)
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Quartz (Chatoyant or Milky variety)
Silicon Dioxide (SiO2)
Chrysocolla
Chrysocolla; (Cu,Al)2H2Si2O5(OH)4·nH2O
Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Chert (specifically Flint or Gray Chert)
Silicon Dioxide (Microcrystalline Quartz), SiO2
Howlite
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Sunstone
Oligoclase or Andesine (Plagioclase Feldspar) - (Ca, Na)((Al, Si)2Si2O8)
Quartz (Peach/Orange variety)
Silicon Dioxide (SiO2)
Chert (often called Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
Peridot
Olivine ((Mg, Fe)2SiO4)
Amber (Black)
Amber (succinite, retinite, etc., specifically, heavily included/dark varieties)
Turquoise (Dyed Howlite or Magnesite imitation)
Hydrated phosphate of copper and aluminum / CuAl6(PO4)4(OH)8·4H2O
Pegmatite (Granitic)
Granitic Pegmatite containing Quartz, Feldspar, and Tourmaline (Schorl)
Nuummite
Nuummite (intergrowth of orthoamphiboles Anthophyllite and Gedrite, (Mg,Fe)7Si8O22(OH)2)
Peridot
Olivine (Mg, Fe)₂SiO₄