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 (Tan/Brown variety) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (Tan/Brown variety)

Chert (Microcrystalline Quartz, SiO2)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Chert (Nodule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Nodule)

Silicon Dioxide (SiO2)

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

Travertine (Tufa)

Chemical Limestone (CaCO3)

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Asphalt / Bituminous Aggregate

Bituminous mixture (Hydrocarbon-based sediment)

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

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Cherty Limestone or Flint) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (Cherty Limestone or Flint)

Microcrystalline Silica (SiO2)

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

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (varietal Chalcedony or Flint) (Silicon dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (varietal Chalcedony or Flint)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Quartz Geode (Silicon Dioxide (SiO2)) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2)

Zebra Jasper (Opaque microcrystalline Quartz (SiO2) with impurities) — sedimentary

Zebra Jasper

Opaque microcrystalline Quartz (SiO2) with impurities

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

Chert (often called Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Limonitic Chert)

Microcrystalline Quartz (SiO2)

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

Chert (Jasper variation)

Silicon Dioxide (SiO2)

Chert (Jasper-rich) (Microcrystalline/Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper-rich)

Microcrystalline/Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (primarily SiO2 - Silicon Dioxide)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Chert with Quartz/Calcite Vein (Microcrystalline Silica (SiO2)) — sedimentary

Chert with Quartz/Calcite Vein

Microcrystalline Silica (SiO2)

Fossil Plant Impression (Calamites) (Calamites sp. (Tracheophyta: Equisetopsida)) — sedimentary

Fossil Plant Impression (Calamites)

Calamites sp. (Tracheophyta: Equisetopsida)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

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

Chert (specifically Flint or Jasper variant)

Microcrystalline Quartz (SiO2)

Limestone (Fossiliferous) (Sedimentary Carbonate Rock (CaCO3)) — sedimentary

Limestone (Fossiliferous)

Sedimentary Carbonate Rock (CaCO3)

Fossilized Shark Tooth (Basal Bone) (Otodus sp. (Mineralized Hydroxyapatite)) — sedimentary

Fossilized Shark Tooth (Basal Bone)

Otodus sp. (Mineralized Hydroxyapatite)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Sulfidic Mudstone with Pyrite/Goethite (Sulfidic Siltstone/Mudstone (FeS2)) — sedimentary

Sulfidic Mudstone with Pyrite/Goethite

Sulfidic Siltstone/Mudstone (FeS2)

Chert (variations include Flint/Jasper) (Cryptocrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (variations include Flint/Jasper)

Cryptocrystalline Silicon Dioxide (SiO2)

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

Chert (Nodule)

Microcrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Chert (Black Chert/Flint)

Cryptocrystalline Quartz (SiO2)

Fossilized Crinoid Stem Segment (Crinoid (Phylum Echinodermata, Class Crinoidea)) — sedimentary

Fossilized Crinoid Stem Segment

Crinoid (Phylum Echinodermata, Class Crinoidea)

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

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (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)

Dinosaur Skull Fossil (Velociraptor Replica) (Velociraptor mongoliensis fossil specimen in sedimentary matrix) — sedimentary

Dinosaur Skull Fossil (Velociraptor Replica)

Velociraptor mongoliensis fossil specimen in sedimentary matrix

Chert (containing Fossil Inclusions) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (containing Fossil Inclusions)

Microcrystalline Quartz (SiO2)

Fossiliferous Limestone (Coquina / Shell Limestone) (Biogenic Limestone (CaCO3)) — sedimentary

Fossiliferous Limestone (Coquina / Shell Limestone)

Biogenic Limestone (CaCO3)

Ferruginous Chert (Microcrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Ferruginous Chert

Microcrystalline Quartz (SiO2) with Iron Oxides

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

Chert Pebble

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified wood (primarily SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)