Amethyst (Raw Quartz)
Silicon Dioxide (SiO2) with iron impurities
Category
Browse organic gemstone (not a mineral) specimens identified by the Rock Identifier community.
Amethyst (Raw Quartz)
Silicon Dioxide (SiO2) with iron impurities
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
Amethyst
Amethyst (Silicon Dioxide, SiO2 + trace Fe3+)
Amethyst
Silicon dioxide (SiO2) with iron impurities
Sunstone
Plagioclase Feldspar ((Ca,Na)(Al,Si)4O8)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)
Chert (often called Flint or Jasper)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Aquamarine
Beryl (Be3Al2Si6O18)
Emerald in Matrix
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Tanzanite
Blue Zoisite (Ca2Al3(SiO4)3(OH))
Pink Spinel
Magnesium Aluminum Oxide (MgAl2O4)
Citrine Quartz
Silicon Dioxide (SiO2)
Amazonite
Microcline (KAlSi3O8)
Rough Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
Amazonite
Potassium aluminum silicate (KAlSi3O8)
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Emerald (Faceted Gemstone)
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Botryoidal Chalcedony
Silicon Dioxide (SiO2)
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Orange Quartz (Citrine Quartz)
Silicon Dioxide (SiO2) with iron impurities
Quartz (Smoky Quartz variant)
Silicon Dioxide (SiO2)
Amethyst (Quartz variety)
Silicon Dioxide (SiO2) with iron impurities
Shungite
Shungite (Non-crystalline carbon, C)
Petrified Wood
Silicified Wood (SiO2 permineralization)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Fossilized Shark Tooth (Basal Bone)
Otodus sp. (Mineralized Hydroxyapatite)
Shungite
Shungite (Non-crystalline carbon, C)
Jasper
Silicon dioxide, SiO2
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Agatized Petrified Wood
Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood
Petrified Wood
Silicified Wood (SiO2)
Amber
Succinite (a Fossilized Tree Resin); Chemical formula is approximately C10H16O
Rhodochrosite
Manganese Carbonate (MnCO3)
Rhodochrosite
Manganese carbonate (MnCO3)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
Petrified Wood
Siliconized Wood (SiO2)
Feldspar
KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8
Fossilized Shark Tooth
Eocene Lamniformes (Mackerel Shark clade)
Fossilized Bone
Vertebrate Fossil Fragment (Calcium Phosphate / Hydroxyapatite)