Rock Identifier

Category

Organic Mineraloid

Browse organic mineraloid specimens identified by the Rock Identifier community.

Learn about Organic Mineraloid in the encyclopedia

Shungite

Sapropel

Bituminous Shale

Bituminous Shale

Black Shale

Petrified Wood

Amber

Jet

Oil Shale

Peat

Pearl

Lizard Skin Jasper

Opalized Wood

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

Chert (Iron-Stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Seashell Fossil (Invertebrate fossil (phylum Mollusca)) — fossil

Seashell Fossil

Invertebrate fossil (phylum Mollusca)

Petrified Wood (Silicified wood / Xylopal) — fossil

Petrified Wood

Silicified wood / Xylopal

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

Limestone Pebble

Calcite-rich Sedimentary Rock (CaCO3)

Agate (Geode/Nodule) (Chalcedony (cryptocrystalline silica, SiO2)) — sedimentary

Agate (Geode/Nodule)

Chalcedony (cryptocrystalline silica, SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossilized Wood (with Coal and Limonite) (Petrified Wood (Silicified or Carbonized Flora)) — sedimentary

Fossilized Wood (with Coal and Limonite)

Petrified Wood (Silicified or Carbonized Flora)

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

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

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

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily Chalcedony or Quartz, SiO2)

Chert (Green variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Green variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Petrified Wood (Agatized/Silicified Wood) (Silicified Wood / Chalcedony (SiO2)) — sedimentary

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood / Chalcedony (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Jasper (Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)) — sedimentary

Jasper

Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)

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

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Chert (Flint)

Chert (Cryptocrystalline variety of Quartz, SiO2)

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

Chert (Chalcedony/Agate)

Microcrystalline Quartz (SiO2)

Fossilized Horn Coral (Rugosa (Tetracoralla)) — fossil

Fossilized Horn Coral

Rugosa (Tetracoralla)

Likely petrified wood or silicified fossil fragment (Silicified wood; predominantly microcrystalline quartz (SiO₂)) — fossil

Likely petrified wood or silicified fossil fragment

Silicified wood; predominantly microcrystalline quartz (SiO₂)

Fossilized Horn Coral (Rugosa (Rugose Coral)) — fossil

Fossilized Horn Coral

Rugosa (Rugose Coral)

Megalodon Shark Tooth (Otodus megalodon) — fossil

Megalodon Shark Tooth

Otodus megalodon

Petrified Wood (Silicified Wood / Xylopal (SiO2)) — fossil

Petrified Wood

Silicified Wood / Xylopal (SiO2)

Septarian Nodule (Septarian Concretion (Calcite, Aragonite, and Limestone)) — sedimentary

Septarian Nodule

Septarian Concretion (Calcite, Aragonite, and Limestone)

Fossil Shark Tooth (Carcharodon carcharias (modern/recent) or similar Lamniform fossil) — fossil

Fossil Shark Tooth

Carcharodon carcharias (modern/recent) or similar Lamniform fossil

Petrified Wood (Silicified Wood (SiO2-dominant)) — fossil

Petrified Wood

Silicified Wood (SiO2-dominant)

Ironstone Concretion (Limonite/Hematite Nodules) (Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)) — sedimentary

Ironstone Concretion (Limonite/Hematite Nodules)

Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)

Jasper (Petrified Wood variant) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Jasper (Petrified Wood variant)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Grey and White Chert (Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Grey and White Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Stromatolite (Jasper-replaced) (Fossilized Stromatolite (Cyanobacteria / Cryptozon / Silica SiO2)) — sedimentary

Stromatolite (Jasper-replaced)

Fossilized Stromatolite (Cyanobacteria / Cryptozon / Silica SiO2)

Quartz Geode (Silicon Dioxide (SiO2) within a secondary sedimentary structure) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2) within a secondary sedimentary structure

Jasper (Red-Brown) (Silicon Dioxide (SiO2) with Iron Oxide impurities) — sedimentary

Jasper (Red-Brown)

Silicon Dioxide (SiO2) with Iron Oxide impurities

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (Quartz Variety) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (Quartz Variety)

Microcrystalline Silica (SiO2)

Chert (specifically Tan/Yellow Chert) (Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (specifically Tan/Yellow Chert)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

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

Chert (Flint Pebbles)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified wood / Xylopal) — fossil

Petrified Wood

Silicified wood / Xylopal

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossiliferous Limestone / Petoskey Stone (Coral Fossil) (Hexagonaria percarinata / Calcite (CaCO3)) — fossil

Fossiliferous Limestone / Petoskey Stone (Coral Fossil)

Hexagonaria percarinata / Calcite (CaCO3)