Petrified Wood
Silicified Wood (SiO2)
metamorphic
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 (Quartz/Chalcedony - SiO2)
mineral
Amber
Succinates (Fossilized Tree Resin)
mineral
Pyrite (Fool's Gold) Cube
Iron Sulfide (FeS2)
mineral
Conglomerate
Conglomerate
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Rose quartz (rough fragment)
Quartz, silicon dioxide (SiO₂), pink variety
mineral
Chert / Chalcedony
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified wood (Quartz / Chalcedonized wood, SiO2)
sedimentary
Fossilized Wood (Petrified Wood)
Agatized wood (primarily SiO2)
fossil
Pink Opal
Amorphous Hydrous Silica (SiO2·nH2O)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Diamond (or Diamond Simulant)
Carbon (C) - Native Element
mineral
Coral Fossil (Petrified Coral)
Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Ironstone Concretion (Moqui Marble / Boji Stone)
Sedimentary Iron Oxide Concretion (Fe2O3 / FeO(OH))
sedimentary
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of cellulose)
fossil
Fossiliferous limestone
Bioclastic carbonate rock; predominantly calcite (CaCO₃)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Rose Quartz
Silicon Dioxide (SiO2)
mineral
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Polished flint/chert pebble
Microcrystalline quartz (SiO₂), commonly called chert or flint
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium and/or Vanadium impurities
mineral
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
sedimentary
Red coral earrings
Corallium rubrum or related precious coral (calcareous coral skeleton; primarily aragonite, CaCO₃)
gemstone
Shark Tooth Fossil
Chondrichthyes (shark) tooth
fossil
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Fossil Shark Tooth
Otodus sp. or Carcharocles sp. (likely fossilized Chondrichthyes)
fossil
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Chert (Jasper)
Silicon dioxide (SiO2)
sedimentary
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous Phosphate of Copper and Aluminum)
mineral
Mixed gemstone bead strand, likely amethyst and assorted colored stones
Likely purple quartz (amethyst, SiO₂) mixed with unidentified green, orange, and reddish beads
gemstone
Slate
Slate (Foliated metamorphic rock)
metamorphic
Fossil Shark Tooth
Carcharodon sp. (likely Otodus or similar Lamniformes order)
sedimentary
Amber
Succinate (Fossilized Tree Resin)
gemstone
Amber / Fossilized Resin
Succinite / Fossilized Tree Resin
mineral
Red heart-shaped glass bead in a wire-wrapped jewelry charm
Likely colored glass (amorphous silica-based material); the image does not show an identifiable geological specimen
gemstone
Emerald in Matrix
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
gemstone
Pyrite
Iron Sulfide (FeS2)
mineral