Rock Identifier

Category

Organic Gemstone (Not A Mineral)

Browse organic gemstone (not a mineral) specimens identified by the Rock Identifier community.

Learn about Organic Gemstone (Not A Mineral) in the encyclopedia

Black Shale

Black Shale

Jet

Jet

Malachite

Malachite

Sapropel

Sapropel

Bituminous Shale

Bituminous Shale

Red Garnet

Red Garnet

Shungite

Shungite

Anatase

Anatase

Sperrylite

Sperrylite

Amber

Amber

Hutcheonite

Hutcheonite

Coal

Coal

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

Amethyst

Amethyst (Silicon Dioxide - SiO2 with iron impurities)

Prehnite (Prehnite (Ca2Al(AlSi3O10)(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

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)

Amethyst (Silicon dioxide / Quartz (SiO2+Fe4+)) — mineral

Amethyst

Silicon dioxide / Quartz (SiO2+Fe4+)

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

Amethyst

Amethyst (Silicon Dioxide, SiO2 with Iron impurities)

Sandstone Concretion (Limonitic Sandstone Concretion) — sedimentary

Sandstone Concretion

Limonitic Sandstone Concretion

Petrified Wood (Silicified Wood (primarily SiO₂ / Silicon Dioxide)) — mineral

Petrified Wood

Silicified Wood (primarily SiO₂ / Silicon Dioxide)

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

Chert (Flint Nodules)

Microcrystalline Quartz (SiO2)

Glauconitic Sandstone (Glauconitic Sandstone (contains (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone

Glauconitic Sandstone (contains (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)

Chert (Commonly known as Flint or Jasper when pigmented) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Commonly known as Flint or Jasper when pigmented)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossil Shark Tooth (Lamniform (Mackerel Shark) fossil tooth, likely Otodus or Cretalamna) — fossil

Fossil Shark Tooth

Lamniform (Mackerel Shark) fossil tooth, likely Otodus or Cretalamna

Petrified Wood (Silicified Wood (primarily Chalcedony or Quartz, SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Chalcedony or Quartz, SiO2)

Fossilized Shark Tooth (Elasmobranchii fossil (likely Odontaspididae family)) — sedimentary

Fossilized Shark Tooth

Elasmobranchii fossil (likely Odontaspididae family)

Petrified Wood (Calamites Fossil) (Calamites sp. (Silicified/Permineralized Plant Fossil)) — sedimentary

Petrified Wood (Calamites Fossil)

Calamites sp. (Silicified/Permineralized Plant Fossil)

Chert (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert

Chert (Microcrystalline Quartz, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossilized Coral (Favosites) (Favosites (extinct genus of tabulate coral)) — sedimentary

Fossilized Coral (Favosites)

Favosites (extinct genus of tabulate coral)

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

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Chert with Quartz Vein (Silicon dioxide (SiO2)) — sedimentary

Chert with Quartz Vein

Silicon dioxide (SiO2)

Sandstone with Vitrinite/Coal inclusions (Arenite with Carbonaceous inclusions) — sedimentary

Sandstone with Vitrinite/Coal inclusions

Arenite with Carbonaceous inclusions

Shungite (Non-crystalline carbon (Fullerene-bearing)) — mineral

Shungite

Non-crystalline carbon (Fullerene-bearing)

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

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Amber (Succinite (fossilized resin)) — mineral

Amber

Succinite (fossilized resin)

Quartz River Pebble with Algae (Silicon Dioxide (SiO2) with organic biofilm) — metamorphic or igneous

Quartz River Pebble with Algae

Silicon Dioxide (SiO2) with organic biofilm

metamorphic or igneous

Sandstone (Ferruginous) (Clastic Sedimentary Rock (Sandstone)) — sedimentary

Sandstone (Ferruginous)

Clastic Sedimentary Rock (Sandstone)

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

Chert Concretion (Flint)

Silicon Dioxide (SiO2)

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

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Travertine (Tufa) (Chemical Sedimentary Rock (CaCO3)) — sedimentary

Travertine (Tufa)

Chemical Sedimentary Rock (CaCO3)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Travertine (Tufa) (Chemical Limestone (CaCO3)) — sedimentary

Travertine (Tufa)

Chemical Limestone (CaCO3)

Asphalt / Bituminous Aggregate (Bituminous mixture (Hydrocarbon-based sediment)) — sedimentary

Asphalt / Bituminous Aggregate

Bituminous mixture (Hydrocarbon-based sediment)

Quartz Geode (Silicon Dioxide (SiO2)) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2)

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

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

Shale (possibly Carbonaceous or Oil Shale) (Laminated Mudstone (primarily clay minerals and quartz)) — sedimentary

Shale (possibly Carbonaceous or Oil Shale)

Laminated Mudstone (primarily clay minerals and quartz)

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

Chert (Jasper variety)

Chert (SiO2)

Tiger Shark Fossil Tooth (Galeocerdo cuvier (fossilized)) — sedimentary

Tiger Shark Fossil Tooth

Galeocerdo cuvier (fossilized)

Green Moss Agate (Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite) — sedimentary

Green Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite

Black Limestone with Calcite Veining (Limestone (CaCO3) with Calcite (CaCO3) inclusions) — sedimentary

Black Limestone with Calcite Veining

Limestone (CaCO3) with Calcite (CaCO3) inclusions

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Green Calcite (Calcium Carbonate (CaCO3)) — mineral

Green Calcite

Calcium Carbonate (CaCO3)