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/Flint Pebble) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Flint Pebble)

Microcrystalline quartz (SiO2)

Chert / Flint (Chert (Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert / Flint

Chert (Cryptocrystalline Quartz, SiO2)

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

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossilized Tiger Shark Tooth (Galeocerdo cuvier (fossilized hydroxylapatite)) — sedimentary

Fossilized Tiger Shark Tooth

Galeocerdo cuvier (fossilized hydroxylapatite)

Chert (variations include Flint or Jasper) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (variations include Flint or Jasper)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert / River Pebble (Silicon Dioxide (SiO2)) — sedimentary

Chert / River Pebble

Silicon Dioxide (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

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

Chert (Tan or Buffer variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Chert (Iron-stained) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Yellow Chert (Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Yellow Chert (Chalcedony)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Chalcedony)

Microcrystalline Quartz (SiO2)

Brown Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Brown Chert

Microcrystalline Quartz (SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Chert (Jasper/Flint variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Chert / Flint (Microcrystalline or cryptocrystalline quartz (SiO2)) — sedimentary

Chert / Flint

Microcrystalline or cryptocrystalline quartz (SiO2)

Chert (with Iron Staining) (Silicon Dioxide (SiO2 / Cryptocrystalline Quartz)) — sedimentary

Chert (with Iron Staining)

Silicon Dioxide (SiO2 / Cryptocrystalline Quartz)

Chert (Jasper/Agate variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Agate variety)

Microcrystalline quartz (SiO2)

Ironstone Concretion (Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)) — sedimentary

Ironstone Concretion

Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)

Septarian Nodule (Calcite-bearing Septarian Concretion) — sedimentary

Septarian Nodule

Calcite-bearing Septarian Concretion

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

Chert (Black Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Chert with Calcite Veins (Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions) — sedimentary

Chert with Calcite Veins

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions

Fossiliferous Limestone (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Fossiliferous Limestone (Coquina) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (Coquina)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Bivalve Fossil (Internal Mold/Steinkern) (Class Bivalvia (Fossilized Mold)) — sedimentary

Bivalve Fossil (Internal Mold/Steinkern)

Class Bivalvia (Fossilized Mold)

Coquina / Shell Limestone (Coquina (Bioclastic Limestone)) — sedimentary

Coquina / Shell Limestone

Coquina (Bioclastic Limestone)

Chert (Flint/Jasper) (Silicon dioxide (SiO2) - Microcrystalline quartz) — sedimentary

Chert (Flint/Jasper)

Silicon dioxide (SiO2) - Microcrystalline quartz

Crushed Limestone (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Crushed Limestone

Sedimentary Calcium Carbonate (CaCO3)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Pyrite on Limestone (Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix) — sedimentary (matrix) / mineral (inclusion)

Pyrite on Limestone

Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix

sedimentary (matrix) / mineral (inclusion)

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (containing Quartz veins) (Chert (SiO2)) — sedimentary

Chert (containing Quartz veins)

Chert (SiO2)

Black Jasper (Black Onyx substitute) (Silicon Dioxide (SiO2) with carbonaceous impurities) — sedimentary (microcrystalline quartz)

Black Jasper (Black Onyx substitute)

Silicon Dioxide (SiO2) with carbonaceous impurities

sedimentary (microcrystalline quartz)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Agatized Petrified Wood (Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood) — metamorphic

Agatized Petrified Wood

Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Chert (Green River Chert)

Microcrystalline Quartz (SiO2)

Chrysoprase (Chalcedony with nickel impurities (SiO2)) — gemstone

Chrysoprase

Chalcedony with nickel impurities (SiO2)

Fossil Coral (Rugose Coral Fragment) (Rugosa (extinct order of solitary and colonial corals)) — sedimentary

Fossil Coral (Rugose Coral Fragment)

Rugosa (extinct order of solitary and colonial corals)

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

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with Bioclasts