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

Opal (Hydrated amorphous silica (SiO2·nH2O)) — mineral

Opal

Hydrated amorphous silica (SiO2·nH2O)

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

Amethyst

Silicon Dioxide with iron impurities (SiO2)

Garnet (Garnet Group (Silicate Minerals), formula varies e.g., Alm: Fe3Al2(SiO4)3) — mineral

Garnet

Garnet Group (Silicate Minerals), formula varies e.g., Alm: Fe3Al2(SiO4)3

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

Peridot

Olivine (Mg, Fe)2SiO4

Aquamarine (Beryl (Be3Al2Si6O18)) — mineral

Aquamarine

Beryl (Be3Al2Si6O18)

Amethyst (Quartz) (Silicon Dioxide (SiO2)) — mineral

Amethyst (Quartz)

Silicon Dioxide (SiO2)

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

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Luminous Stone (Glow-in-the-dark Synthetic/Man-made Stone) (Strontium Aluminate tinted glass or resin (Crystalline silicate/oxide mix)) — mineral (synthetic)

Luminous Stone (Glow-in-the-dark Synthetic/Man-made Stone)

Strontium Aluminate tinted glass or resin (Crystalline silicate/oxide mix)

mineral (synthetic)

Orthoclase Feldspar (Potassium Feldspar (KAlSi3O8)) — mineral

Orthoclase Feldspar

Potassium Feldspar (KAlSi3O8)

Sapphire in a ring (Corundum (Al2O3)) — mineral

Sapphire in a ring

Corundum (Al2O3)

Yellow Quartz (Citrine/Yellow Jasper mix) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine/Yellow Jasper mix)

Silicon Dioxide (SiO2)

Amethyst (Rough Crystal) (Silicon Dioxide (SiO2 with ferric iron impurities)) — mineral

Amethyst (Rough Crystal)

Silicon Dioxide (SiO2 with ferric iron impurities)

Amazonite (Microcline (KAlSi3O8)) — mineral

Amazonite

Microcline (KAlSi3O8)

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

Peridot (Olivine)

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

Chert (Smooth River Pebble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Smooth River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper with Quartz Vein (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Jasper with Quartz Vein

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert (Jasper-bearing) (Silicon dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Jasper-bearing)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Graphite-veined Quartzite (Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)) — metamorphic

Graphite-veined Quartzite

Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)

Fossil Coral (Favosites Honeycomb) (Favosites (Genus), Phylum Cnidaria, Class Anthozoa) — sedimentary

Fossil Coral (Favosites Honeycomb)

Favosites (Genus), Phylum Cnidaria, Class Anthozoa

Jasper (Iron-stained Chert) (Silicon Dioxide (SiO2) with impurities of Hematite or Goethite) — sedimentary

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with impurities of Hematite or Goethite

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Rhodochrosite (Manganese Carbonate (MnCO3)) — mineral

Rhodochrosite

Manganese Carbonate (MnCO3)

Red Jasper (Silicon Dioxide with Iron inclusions (SiO2)) — sedimentary

Red Jasper

Silicon Dioxide with Iron inclusions (SiO2)

Fairburn Agate (Cryptocrystalline Quartz (SiO2)) — mineral

Fairburn Agate

Cryptocrystalline Quartz (SiO2)

Red Jasper (Jasper (Silicon Dioxide with Hematite inclusions), SiO2) — sedimentary

Red Jasper

Jasper (Silicon Dioxide with Hematite inclusions), SiO2

Rhodochrosite (Manganese carbonate (MnCO3)) — mineral

Rhodochrosite

Manganese carbonate (MnCO3)

Amazonite (Microcline (KAlSi3O8 variant)) — mineral

Amazonite

Microcline (KAlSi3O8 variant)

Jasper (Multi-color Chert) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper (Multi-color Chert)

Silicon Dioxide (SiO2) with impurities

Rhodonite (Rhodonite (Manganese Iron Magnesium Calcium Silicate - (Mn,Fe,Mg,Ca)SiO3)) — mineral

Rhodonite

Rhodonite (Manganese Iron Magnesium Calcium Silicate - (Mn,Fe,Mg,Ca)SiO3)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Agate (or Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Agate (or Chalcedony)

Silicon Dioxide (SiO2)

Jasper (Red Jasper) (Silicon Dioxide (SiO₂)) — sedimentary

Jasper (Red Jasper)

Silicon Dioxide (SiO₂)

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

Red Jasper

Jasper (Silicon Dioxide, SiO2)

Silicon Carbide (Carborundum) (Silicon Carbide (SiC) / Moissanite (natural)) — mineral

Silicon Carbide (Carborundum)

Silicon Carbide (SiC) / Moissanite (natural)

Green Tourmaline (Elbaite (part of Tourmaline group), Na(Li1.5Al1.5)Al6Si6O18(BO3)3(OH)4) — mineral

Green Tourmaline

Elbaite (part of Tourmaline group), Na(Li1.5Al1.5)Al6Si6O18(BO3)3(OH)4

Moonstone (specifically Cat's Eye or Gray Moonstone) (Orthoclase (Potassium Aluminum Silicate) with the formula (K,Na)AlSi3O8) — mineral

Moonstone (specifically Cat's Eye or Gray Moonstone)

Orthoclase (Potassium Aluminum Silicate) with the formula (K,Na)AlSi3O8

Moonstone (Feldspar variety) (Orthoclase Feldspar (KAlSi3O8)) — mineral

Moonstone (Feldspar variety)

Orthoclase Feldspar (KAlSi3O8)

Pearl (Aragonite / Calcium Carbonate (CaCO3)) — mineraloid

Pearl

Aragonite / Calcium Carbonate (CaCO3)