Rock Identifier

Category

Organic (Anthropogenic)

Browse organic (anthropogenic) specimens identified by the Rock Identifier community.

Learn about Organic (Anthropogenic) in the encyclopedia

Sapropel

Bituminous Shale

Bituminous Shale

Black Shale

Petrified Wood

Amber

Jet

Peat

Oil Shale

Pearl

Lizard Skin Jasper

Opalized Wood

Coral Rock

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)

Greenstone / Chert (Cryptocrystalline Quartz (SiO2) or Altered Basalt) — sedimentary or metamorphic

Greenstone / Chert

Cryptocrystalline Quartz (SiO2) or Altered Basalt

sedimentary or metamorphic

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (specifically Flint or Common Chert)

Silicon Dioxide (SiO2)

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

Chert (and Flint)

Silicon Dioxide (SiO2)

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

Chert (with Quartz veins)

Microcrystalline Quartz (SiO2)

Ironstone Concretion (Iron-rich Mudstone) (Siderite / Geothite concretion (FeCO3 / FeO(OH))) — sedimentary

Ironstone Concretion (Iron-rich Mudstone)

Siderite / Geothite concretion (FeCO3 / FeO(OH))

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

Chert (and Petrified Wood)

Silicon Dioxide (SiO2)

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

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 principal component)

Fossil-bearing sedimentary rock, possibly fossil wood or bone (Indeterminate silicified/carbonate fossil in sandstone or mudstone) — fossil

Fossil-bearing sedimentary rock, possibly fossil wood or bone

Indeterminate silicified/carbonate fossil in sandstone or mudstone

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Fossilized Shark Tooth (Chondrichthyes tooth) — fossil

Fossilized Shark Tooth

Chondrichthyes tooth

Elephant Skin Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Elephant Skin Jasper

Microcrystalline Quartz (SiO2)

Shark Tooth Fossil (Chondrichthyes (class) fossilized tooth) — fossil

Shark Tooth Fossil

Chondrichthyes (class) fossilized tooth

Fossilized Horse Tooth (Equus sp. (fossilized molar)) — fossil

Fossilized Horse Tooth

Equus sp. (fossilized molar)

Limestone (Calcareous sedimentary rock (CaCO3)) — sedimentary

Limestone

Calcareous sedimentary rock (CaCO3)

Rough Chalcedony / Jasper Agate Nodule (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Rough Chalcedony / Jasper Agate Nodule

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Petrified Wood (Silicified Wood (Silicon Dioxide - SiO2)) — fossil

Petrified Wood

Silicified Wood (Silicon Dioxide - SiO2)

Limestone (River Pebble / Fossiliferous Limestone) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (River Pebble / Fossiliferous Limestone)

Calcium Carbonate (CaCO3)

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

Limestone Pebble

Calcite-rich Sedimentary Rock (CaCO3)

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

Chert (potentially Jasper)

Microcrystalline Quartz (SiO2)

Mammoth or Mastodon Tooth Fossil (Proboscidea tooth (Mammuthus or Mammut)) — fossil

Mammoth or Mastodon Tooth Fossil

Proboscidea tooth (Mammuthus or Mammut)

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

Chert (and Flint)

Silicon Dioxide (SiO2)

Anthracite Coal (Anthracite (Highly Metamorphosed Coal)) — sedimentary

Anthracite Coal

Anthracite (Highly Metamorphosed Coal)

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

Chert (Fossiliferous Chert/Flint)

Silicon Dioxide (SiO2)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

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) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Flint) with Iron Staining (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint) with Iron Staining

Microcrystalline Quartz (SiO2)

Chert (Flint) (Silicon dioxide (SiO2)) — sedimentary

Chert (Flint)

Silicon dioxide (SiO2)

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

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Septarian Nodules-like) (Silicon dioxide (SiO2)) — sedimentary

Chert (Septarian Nodules-like)

Silicon dioxide (SiO2)

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

Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Chert

Chert (Microcrystalline Quartz, SiO2)

Chert (often called Jasper or Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Jasper or Flint)

Silicon Dioxide (SiO2)

Anthracite Coal (Anthracite) — sedimentary

Anthracite Coal

Anthracite

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

Sandstone (Ferruginous)

Clastic Sedimentary Rock (Sandstone)

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

Chert (Flint Nodules)

Silicon Dioxide (SiO2)

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

Chert Concretion (Flint)

Silicon Dioxide (SiO2)

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

Chert (Flint)

Silicon Dioxide (SiO2)