Rock Identifier

Category

Organic Gemstone

Browse organic gemstone specimens identified by the Rock Identifier community.

Learn about Organic Gemstone in the encyclopedia

Jet

Jet

Sapropel

Sapropel

Red Garnet

Red Garnet

Bituminous Shale

Bituminous Shale

Black Shale

Black Shale

Petrified Wood

Petrified Wood

Amber

Amber

Peat

Peat

Oil Shale

Oil Shale

Pearl

Pearl

Lizard Skin Jasper

Lizard Skin Jasper

Rhodonite

Rhodonite

Chert (Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified wood (Quartz, SiO2)) — metamorphic

Petrified Wood

Silicified wood (Quartz, SiO2)

Chert (and Limestone) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and Limestone)

Silicon Dioxide (SiO2)

Chert (specifically a fragment with Desert Varnish) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (specifically a fragment with Desert Varnish)

Microcrystalline quartz (SiO2)

Chert (Grey Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Grey Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (and Flint) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (and Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Jasper/Flint variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

Chert Nodules (Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Nodules (Jasper)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (specifically Black Chert or Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Black Chert or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Crinoid Fossil in Limestone (Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)) — sedimentary

Crinoid Fossil in Limestone

Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)

Shale (possibly Carbonaceous or Oil Shale) (Argillaceous Sedimentary Rock) — sedimentary

Shale (possibly Carbonaceous or Oil Shale)

Argillaceous Sedimentary Rock

Limestone (Porous/Travertine variant) (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Porous/Travertine variant)

Sedimentary Calcium Carbonate (CaCO3)

Petrified Wood (Silicified wood (Quartz/Chalcedony replacement) SiO2) — sedimentary

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement) SiO2

Chert (often called Flint or Jasper) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (White-Tan variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White-Tan variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sandstone (Arenicola (comprising mostly Quartz, SiO2)) — sedimentary

Sandstone

Arenicola (comprising mostly Quartz, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (primarily SiO₂)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO₂)

Chert Pebble (Chert (composed primarily of Microcrystalline Quartz, SiO2)) — sedimentary

Chert Pebble

Chert (composed primarily of Microcrystalline Quartz, SiO2)

Chert (Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint)

Silicon Dioxide (SiO2)

Yellow Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Yellow Jasper

Jasper (Silicon Dioxide, SiO2)

Black Jasper (Black Stone / River Pebble) (Silicon Dioxide (SiO₂), Opaque variety of Chalcedony) — sedimentary

Black Jasper (Black Stone / River Pebble)

Silicon Dioxide (SiO₂), Opaque variety of Chalcedony

Coprolite (Fossilized Feces) — sedimentary

Coprolite

Fossilized Feces

Tufa (Calcareous Tufa (Calcium Carbonate, CaCO3)) — sedimentary

Tufa

Calcareous Tufa (Calcium Carbonate, CaCO3)

Fossilized Shark Tooth (Fossilized elasmobranch tooth (Apatite/Calcium Phosphate)) — sedimentary

Fossilized Shark Tooth

Fossilized elasmobranch tooth (Apatite/Calcium Phosphate)

Fossilized Megalodon Tooth Fragment (Otodus megalodon (Carcharocles megalodon fossil)) — sedimentary

Fossilized Megalodon Tooth Fragment

Otodus megalodon (Carcharocles megalodon fossil)

Petrified Wood (Silicified Wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — gemstone

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Emerald (Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities) — gemstone

Emerald

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Emerald (Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities) — gemstone

Emerald

Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities

Diamond (Cut Gemstone) (Natural Carbon (C)) — gemstone

Diamond (Cut Gemstone)

Natural Carbon (C)

Diamond (Cut Gemstone) (Carbon (C)) — gemstone

Diamond (Cut Gemstone)

Carbon (C)

Peridot (Olivine ((Mg, Fe)2SiO4)) — mineral

Peridot

Olivine ((Mg, Fe)2SiO4)

Moss Agate (Silicon Dioxide (SiO2) with inclusions) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions

Jasper (Silicon dioxide (SiO2)) — Mineral / Sedimentary

Jasper

Silicon dioxide (SiO2)

Mineral / Sedimentary

Garnet (Garnet Group (Silicate Minerals)) — mineral

Garnet

Garnet Group (Silicate Minerals)

Almandine Garnet (Almandine (Fe3Al2(SiO4)3)) — mineral

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Turquoise (Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)) — mineral

Turquoise

Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)

Diamond (Cut Gemstones in Jewelry) (Carbon (C)) — gemstone

Diamond (Cut Gemstones in Jewelry)

Carbon (C)

Garnet (Garnet group (X3Y2(SiO4)3)) — mineral

Garnet

Garnet group (X3Y2(SiO4)3)