Petrified Wood
Silicified wood (primarily Quartz, SiO2)
fossil
Category
Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)
Browse organic gemstone (not a rock or mineral in the traditional sense, but bio mineralized material) specimens identified by the Rock Identifier community.
Learn about Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material) in the encyclopedia
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Petrified Wood
Silicified Wood (SiO2)
sedimentary
Blue Topaz
Aluminum silicate fluoride hydroxide (Al2SiO4(F,OH)2)
gemstone
Smoky Quartz (Tumbled)
Silicon Dioxide (SiO2)
mineral
Pearl (Cultured Freshwater)
Calcium Carbonate (Aragonite) - CaCO3
mineral
Fossil gastropod in granite-like stone
Gastropoda indet.; enclosing rock likely polished granite or gneiss
fossil
Brecciated quartz-rich rock (probable vein breccia)
Hydrothermal quartz breccia; predominantly SiO₂ quartz clasts in iron-oxide-rich cement
igneous
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
mineral
Red Coral
Corallium rubrum
gemstone
Iron-stained quartz vein fragment
Quartz (SiO₂), likely with limonite/goethite iron oxides and minor sulfides
mineral
Fire Opal (in Matrix)
Hydrated Silica (SiO2·nH2O)
mineral
Fossilized Shark Tooth
Chondrichthyes (class) fossilized tooth
fossil
Sandstone (likely Arkose or Quartz Sandstone)
Arenite (SiO2 principal component)
sedimentary
Tumbled Rose Quartz
Silicon Dioxide (SiO2)
mineral
Jasper
Silicon dioxide (Microcrystalline quartz, SiO2)
mineral
Pearl
Aragonite and Calcite (CaCO3) with Conchiolin
mineral
Iron-stained quartz-bearing rock (probable weathered quartz vein or ironstone)
Quartz (SiO₂) with goethite/limonite iron oxides; possibly altered volcanic or metamorphic host rock
mineral
Ruby
Corundum (Al2O3 with chromium trace elements)
gemstone
Moonstone
Orthoclase (KAlSi3O8), specifically the variety showing adularescence
mineral
Fossilized Shark Tooth
Selachimorpha fossil
fossil
Fossilized Bivalve Shell
Bivalvia (Phylum Mollusca)
fossil
Coprolite
Fossilized Feces
fossil
Flint / Chert with Cortex
Microcrystalline Quartz (SiO2)
sedimentary
Angelite
Anhydrite (Calcium Sulfate, CaSO4)
mineral
Fire Opal (in matrix)
Hydrated Silica (SiO2·nH2O)
Mineraloid
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Petrified Wood
Silicified Wood (SiO2)
fossil
Green Jasper
Microcrystalline Quartz (SiO2) with mineral inclusions
sedimentary
Amber
Succinite (fossilized resin, C10H16O)
mineral
Petrified Wood
Silicified Wood (SiO2)
fossil
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
mineral
Pearl
Calcium carbonate (CaCO3) - mainly Aragonite
mineral
Tiger's Eye
Titanium-containing Quartz (Silica: SiO2)
Mineral
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Raw Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
mineral
Jade (likely Jadeite)
Jadeite (a pyroxene mineral) or Nephrite (a variety of amphibole mineral)
Mineral
Blue Zircon
Zircon (Zirconium Silicate, ZrSiO4)
gemstone
Fossil Shark Tooth
Chondrichthyes (Class)
fossil
Pearl
Biogenic Calcium Carbonate (Aragonite and Conchiolin), CaCO3
mineral
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)
sedimentary
Fossilized tooth, likely mammoth or mastodon molar fragment
Proboscidean molar enamel and dentin; Mammuthus or Mammut sp. (tentative)
fossil