Petrified Wood
Silicified wood (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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Ruby
Corundum (Al2O3)
mineral
Tree Agate (or Moss Agate)
Dendritic Agate (Silicon Dioxide - SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Dendritic Agate (Tree Agate)
Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions
mineral
Herkimer Diamond
Quartz (Silica - SiO2)
mineral
Bloodstone (Heliotrope)
Cryptocrystalline Quartz (SiO2 with inclusions of Iron Oxide/Chlorite)
mineral
Red Sandstone
Arenite (Iron-rich Sandstone)
sedimentary
Chert (Flint Pebbles)
Microcrystalline Quartz (SiO2)
sedimentary
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Metal Alloy (Jewelry)
Not a naturally occurring rock or mineral; likely a metal alloy for jewelry. Possible compositions include sterling silver (92.5% silver, 7.5% copper), or other silver/gold alloys.
Man-made Material (jewelry, metal alloy)
Aquamarine
Beryl (Be3Al2Si6O18)
mineral
Amber / Copal
Fossilized Tree Resin (Succinate)
Mineraloid
Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
fossil
Iron-stained quartz (likely quartz-rich vein rock)
Quartz, SiO₂, with iron-oxide/hydroxide staining (limonite/goethite)
mineral
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
mineral
Polished bloodstone (heliotrope), likely
Cryptocrystalline quartz (chalcedony, SiO₂) with iron-oxide inclusions
mineral
Bloodstone
Heliotrope (a variety of Chalcedony, SiO₂ with inclusions)
Metamorphic Rock
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium), CuAl6(PO4)4(OH)8·4H2O
mineral
Chert (Yellow/Tan)
Microcrystalline Quartz (SiO2)
sedimentary
Polished banded agate (likely picture jasper or petrified wood)
Microcrystalline quartz, SiO₂, with iron-oxide and clay inclusions
gemstone
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Aquamarine
Beryl (Be3Al2Si6O18)
mineral
Heliotrope (Bloodstone)
Silicon dioxide (SiO2) with inclusions of Hematite or Chlorite
Mineral
Yellow Agate (Aqeeq / Chalcedony)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Tumbled amethyst
Amethyst, purple variety of quartz (SiO₂)
mineral
Chert (White-Tan variety)
Silicon dioxide (SiO2) / Microcrystalline Quartz
sedimentary
Green glass-like cabochon, likely synthetic glass or resin
Unidentified green transparent material; possibly molded glass, synthetic spinel, or resin
gemstone
Chert (Jasper-rich)
Silicon Dioxide (SiO2)
sedimentary
Polished moss agate / dendritic agate
Microcrystalline quartz (SiO₂) with iron- and manganese-oxide inclusions
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz vein rock with iron-stained matrix
Quartz (SiO₂), likely with limonite/goethite and minor feldspar or mica
mineral
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal)
sedimentary
Chert / Flint
Cryptocrystalline Quartz (SiO2)
sedimentary
Goldstone (brown goldstone)
Man-made aventurine glass, typically copper-bearing silica glass
gemstone
Weathered quartz-rich pebble (probable quartzite or quartz vein material)
Quartzite, predominantly SiO₂ (identification provisional)
metamorphic
Rough Amethyst
Silicon Dioxide (SiO2) with Iron impurities
mineral
Polished carnelian/chalcedony
Carnelian, a reddish-orange variety of microcrystalline quartz (SiO₂)
mineral
Moonstone
Adularia (Potassium Aluminum Silicate, KAlSi3O8)
mineral