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

Charoite (Charoite (K(Ca,Na)2Si4O10(OH,F)·H2O)) — mineral

Charoite

Charoite (K(Ca,Na)2Si4O10(OH,F)·H2O)

Turquoise (Turquoise (CuAl6(PO4)4(OH)8·4H2O)) — mineral

Turquoise

Turquoise (CuAl6(PO4)4(OH)8·4H2O)

Amethyst (Quartz) (Amethyst (Silicon Dioxide with Iron impurities), SiO2) — mineral

Amethyst (Quartz)

Amethyst (Silicon Dioxide with Iron impurities), SiO2

Hardened Gray Mudstone (Argillite / Silicified Mudstone (principally SiO2 and Al2Si2O5(OH)4)) — sedimentary

Hardened Gray Mudstone

Argillite / Silicified Mudstone (principally SiO2 and Al2Si2O5(OH)4)

Yellow Quartz (Citrine or Iron-stained Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood) (Silicified Wood (primarily Chalcedony/Quartz, SiO2)) — mineral

Petrified Wood (Silicified Wood)

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Petrified Wood (Silicified Wood (SiO2 - Silicon Dioxide)) — mineral

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Petrified Wood (Silicified Wood (SiO2 - Silicon Dioxide)) — mineral

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Petrified Wood (Silicified wood (primarily Silicon Dioxide - SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily Silicon Dioxide - SiO2)

Gastropod Fossil (Internal Mold) (Phylum Mollusca, Class Gastropoda (Steinkern)) — sedimentary

Gastropod Fossil (Internal Mold)

Phylum Mollusca, Class Gastropoda (Steinkern)

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

Chert (specifically Jasper or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Cordierite in Matrix (Iolite) (Magnesium iron aluminium cyclosilicate (Mg,Fe)2Al4Si5O18) — metamorphic

Cordierite in Matrix (Iolite)

Magnesium iron aluminium cyclosilicate (Mg,Fe)2Al4Si5O18

Peridot (Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)) — mineral

Peridot

Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)

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

Peridot (Olivine)

Olivine ((Mg, Fe)2SiO4)

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

Turquoise

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

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

Turquoise

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

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

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

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

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

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

Turquoise

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

Red Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Fairburn Agate (Cryptocrystalline Quartz (SiO2) with trace Iron Oxides) — mineral

Fairburn Agate

Cryptocrystalline Quartz (SiO2) with trace Iron Oxides

Rhodonite (Manganese Silicate (Mn,Fe,Mg,Ca)SiO3) — mineral

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

Unakite (Epidotized Granite (composition: K-feldspar, Epidote, and Quartz)) — metamorphic

Unakite

Epidotized Granite (composition: K-feldspar, Epidote, and Quartz)

Rhodonite (Manganese silicate (Mn,Fe,Mg,Ca)SiO3) — mineral

Rhodonite

Manganese silicate (Mn,Fe,Mg,Ca)SiO3

Smoky Quartz (Smoky Quartz (Silicon Dioxide - SiO2)) — mineral

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Red Jasper (Jasper (SiO2 with Fe2O3 inclusions)) — sedimentary

Red Jasper

Jasper (SiO2 with Fe2O3 inclusions)

Carnelian and White Quartz Bracelet (Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz) — mineral

Carnelian and White Quartz Bracelet

Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz

Diamond (in Jewelry) (Carbon (C)) — mineral

Diamond (in Jewelry)

Carbon (C)

Rhodochrosite (Manganese carbonate (MnCO3)) — mineral

Rhodochrosite

Manganese carbonate (MnCO3)

Bituminous Coal (Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)) — sedimentary

Bituminous Coal

Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)

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

Peridot

Olivine (Mg, Fe)2SiO4

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)

Carnelian Agate (Silicon dioxide (SiO2) - Chalcedony variety) — mineral

Carnelian Agate

Silicon dioxide (SiO2) - Chalcedony variety

Peridot (Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)) — mineral

Peridot

Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)

Green Quartz (Prasiolite) (Crystalline Silicon Dioxide (SiO2) with iron impurities) — mineral

Green Quartz (Prasiolite)

Crystalline Silicon Dioxide (SiO2) with iron impurities

Citrine Quartz (Silicon Dioxide (SiO2) with iron impurities) — mineral

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

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

Turquoise

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

Jasper (Silicon Dioxide (SiO2)) — sedimentary

Jasper

Silicon Dioxide (SiO2)

Olivine (Peridot) (Olivine (Magnesium Iron Silicate, (Mg,Fe)2SiO4)) — mineral

Olivine (Peridot)

Olivine (Magnesium Iron Silicate, (Mg,Fe)2SiO4)

Olivine (Peridot) (Magnesium Iron Silicate (Mg, Fe)2SiO4) — mineral

Olivine (Peridot)

Magnesium Iron Silicate (Mg, Fe)2SiO4

Amethyst (Pale/Light Variety) (Quartz (Silicon Dioxide) with Iron impurities - SiO2) — mineral

Amethyst (Pale/Light Variety)

Quartz (Silicon Dioxide) with Iron impurities - SiO2