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 (variations include Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (variations include Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Nodule)

Microcrystalline Quartz (SiO2)

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

Chert (often called Flint or Jasper when pigmented)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Sandstone (likely Arkose or Quartz Sandstone) (Arenite (SiO2 principal component)) — sedimentary

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 principal component)

Chert (and Petrified Wood) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and Petrified Wood)

Silicon Dioxide (SiO2)

Garnet (Pyrope or Almandine (X3Y2(SiO4)3)) — mineral

Garnet

Pyrope or Almandine (X3Y2(SiO4)3)

Larimar (Pectolite, NaCa2Si3O8(OH)) — gemstone

Larimar

Pectolite, NaCa2Si3O8(OH)

Amber (Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)) — mineral

Amber

Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)

Dendritic Agate / Moss Agate (Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions) — mineral

Dendritic Agate / Moss Agate

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

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

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

Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite

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

Petrified Wood

Silicified Wood (primarily SiO2)

Moss Agate (Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions) — mineral

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions

Shale (Clastic sedimentary rock (primarily clay and silt minerals)) — sedimentary

Shale

Clastic sedimentary rock (primarily clay and silt minerals)

Aquamarine (Beryl (Be3Al2Si6O18)) — mineral

Aquamarine

Beryl (Be3Al2Si6O18)

Fossil Coral (Rugosa or Solitary Coral) (Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)) — sedimentary

Fossil Coral (Rugosa or Solitary Coral)

Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)

Chert (Holey Stone) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Holey Stone)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Fossiliferous Limestone (Calcium Carbonate (CaCO3) with Bioclasts) — sedimentary

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with Bioclasts

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

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

Peridot

Olivine (Mg, Fe)2SiO4

Black Onyx (Cryptocrystalline Quartz (SiO2 with organic/iron impurities)) — mineral

Black Onyx

Cryptocrystalline Quartz (SiO2 with organic/iron impurities)

Blue Agate (Tumbled and Dyed) (Silicon Dioxide (SiO2) with likely organic dyes) — mineral

Blue Agate (Tumbled and Dyed)

Silicon Dioxide (SiO2) with likely organic dyes

Quartz Pebble (Citrine or Iron-Stained) (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble (Citrine or Iron-Stained)

Silicon Dioxide (SiO2)

Sunstone (Feldspar variety) ((Ca,Na)(Al,Si)4O8 with Hematite or Goethite inclusions) — mineral

Sunstone (Feldspar variety)

(Ca,Na)(Al,Si)4O8 with Hematite or Goethite inclusions

Diamond in Gold Setting (Diamond (C - pure carbon)) — mineral

Diamond in Gold Setting

Diamond (C - pure carbon)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Fossiliferous Limestone (Sedimentary rock containing Indeterminate Fossil remains (likely Crinoid stem or Bryozoan fragment)) — fossil

Fossiliferous Limestone

Sedimentary rock containing Indeterminate Fossil remains (likely Crinoid stem or Bryozoan fragment)

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

Chert (Flint Nodules)

Silicon Dioxide (SiO2)

Anthracite Coal (Anthracite) — sedimentary

Anthracite Coal

Anthracite

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 (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (Jasper-like Silicate) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper-like Silicate)

Microcrystalline quartz (SiO2)

Chert (specifically Flint or Gray Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Gray Chert)

Silicon Dioxide (SiO2)

Fancy Jasper (Agate/Chert mix) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Fancy Jasper (Agate/Chert mix)

Silicon Dioxide (SiO2) with impurities

Chert (varietal: Jasper or Ironstone nodule) (Microcrystalline Quartz (SiO2) with iron oxides) — sedimentary

Chert (varietal: Jasper or Ironstone nodule)

Microcrystalline Quartz (SiO2) with iron oxides

Fossiliferous Limestone (Gritstone/Marl) (CaCO3 (Calcium Carbonate) with Fossil Inclusions) — sedimentary

Fossiliferous Limestone (Gritstone/Marl)

CaCO3 (Calcium Carbonate) with Fossil Inclusions

Chert (River Pebble) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Sandstone with Iron Staining (Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone with Iron Staining

Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)

Chert (and Quartz Gravel) (Chert (Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (and Quartz Gravel)

Chert (Cryptocrystalline Quartz, SiO2)