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 (Yellow Chert/Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Chert/Flint)

Silicon Dioxide (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Jasper-Agate (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Jasper-Agate

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

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

Chert (Jasper/Flint Pebble)

Microcrystalline quartz (SiO2)

Fossilized Brain Coral (Diploria labyrinthiformis (Fossilized)) — sedimentary

Fossilized Brain Coral

Diploria labyrinthiformis (Fossilized)

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

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

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

Chert (Jasper focus)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Jasper (specifically a banded or dark variety) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper (specifically a banded or dark variety)

Silicon Dioxide (SiO2) with impurities

Fossiliferous Siltstone (Clastic Sedimentary Rock with Fossil Inclusions) — sedimentary

Fossiliferous Siltstone

Clastic Sedimentary Rock with Fossil Inclusions

Chert (with Quartz veins) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (with Quartz veins)

Microcrystalline quartz (SiO2)

Chert (Yellow/Tan Variety) (Chert (SiO2)) — sedimentary

Chert (Yellow/Tan Variety)

Chert (SiO2)

Fossiliferous Limestone (Crinoidal) (Calcite-bearing bioclastic packstone (CaCO3)) — sedimentary

Fossiliferous Limestone (Crinoidal)

Calcite-bearing bioclastic packstone (CaCO3)

Chert Fossil (Pebble) (Microcrystalline Quartz (SiO2) with biogenic inclusions) — sedimentary

Chert Fossil (Pebble)

Microcrystalline Quartz (SiO2) with biogenic inclusions

Chert (specifically Tan/Yellow Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Tan/Yellow Chert)

Silicon Dioxide (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossilized Bone Fragment (Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)) — sedimentary

Fossilized Bone Fragment

Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)

Chert (within Asphalt) (Chert (SiO2)) — sedimentary

Chert (within Asphalt)

Chert (SiO2)

Fossiliferous Limestone (Calcite-rich Sedimentary Rock (CaCO3)) — sedimentary

Fossiliferous Limestone

Calcite-rich Sedimentary Rock (CaCO3)

Chert (Flint) with Limestone Matrix (Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)) — sedimentary

Chert (Flint) with Limestone Matrix

Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)

Chert (specifically Flint or Gray Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Gray Chalcedony)

Microcrystalline Quartz (SiO2)

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

Chert (specifically Flint or Common Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Travertine (Tufa)

Chemical Sedimentary Rock (CaCO3)

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

Chert (often called Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Crinoid Stem Fragment (Crinoid (Phylum Echinodermata, Class Crinoidea)) — sedimentary

Crinoid Stem Fragment

Crinoid (Phylum Echinodermata, Class Crinoidea)

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

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Chert (and/or Flint) (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert (and/or Flint)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Jasper (Cryptocrystalline Quartz (SiO2)) — sedimentary

Jasper

Cryptocrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Blue or Grey Chert/Flint) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Blue or Grey Chert/Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (varietal: Flint or River Pebble) (Silicon Dioxide (SiO₂)) — sedimentary

Chert (varietal: Flint or River Pebble)

Silicon Dioxide (SiO₂)

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

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)

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

Chert (Jasper/Agate variety)

Silicon Dioxide (SiO2)

Chert (often called Flint when dark) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Orthoceras Fossil Limestone (Orthoceras sp. (Calcium Carbonate, CaCO3)) — sedimentary

Orthoceras Fossil Limestone

Orthoceras sp. (Calcium Carbonate, CaCO3)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Chert (Quartz Variety) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Quartz Variety)

Chert (Silicon Dioxide, SiO2)

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

Chert / Jasper / Agate (Chalcedony Group)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint variant) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Jasper/Flint variant)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (often called Flint or River Rock) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or River Rock)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)