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

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

Petrified Wood

Silicified wood (primarily SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Chert (Green 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)

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

Petrified Wood

Silicified wood (primarily SiO2)

Chert (specifically Green Chert/Jasper) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (specifically Green Chert/Jasper)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Shungite (Non-crystalline carbon (similar to anthracite coal or meta-anthracite)) — metamorphic

Shungite

Non-crystalline carbon (similar to anthracite coal or meta-anthracite)

Chert Concretion with Iron Oxide Staining (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Concretion with Iron Oxide Staining

Microcrystalline Quartz (SiO2)

Black Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Black Jasper

Jasper (Silicon Dioxide, SiO2)

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

Chert (River Pebble)

Microcrystalline silica (SiO2)

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

Chert (Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (and Limestone) (Silicon Dioxide (SiO2) in Calcium Carbonate (CaCO3)) — sedimentary

Chert (and Limestone)

Silicon Dioxide (SiO2) in Calcium Carbonate (CaCO3)

Chert with Iron Oxide Staining (Microcrystalline Quartz (SiO2) with Limonite/Goethite staining) — sedimentary

Chert with Iron Oxide Staining

Microcrystalline Quartz (SiO2) with Limonite/Goethite staining

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

Chert (Iron-stained variant)

Microcrystalline Quartz (SiO2)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

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

Chert (Jasper)

Silicon Dioxide (SiO2)

Fossilized Oyster Shell (Limestone/Coquina) (Crassostrea (Fossilized Bivalve), Calcium Carbonate (CaCO3)) — sedimentary

Fossilized Oyster Shell (Limestone/Coquina)

Crassostrea (Fossilized Bivalve), Calcium Carbonate (CaCO3)

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

Chert (often called Flint)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Peridot (Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)) — mineral

Peridot

Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)

Chert (Polished/Tumbled) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Polished/Tumbled)

Silicon Dioxide (SiO2)

Tufa (Calcareous Tufa) (Calcareous Tufa (Precipitated CaCO3)) — sedimentary

Tufa (Calcareous Tufa)

Calcareous Tufa (Precipitated CaCO3)

Amber (Succinite (fossilized resin)) — mineraloid

Amber

Succinite (fossilized resin)

River Pebble (Siltstone/Mudstone) (Clastic sedimentary rock) — sedimentary

River Pebble (Siltstone/Mudstone)

Clastic sedimentary rock

Amber (Succinite (fossilized resin); C10H16O) — mineraloid

Amber

Succinite (fossilized resin); C10H16O

Amber (Succinite (Fossilized Tree Resin)) — Organic Mineraloid

Amber

Succinite (Fossilized Tree Resin)

Organic Mineraloid

Jasper with Agate and Quartz Inclusions (Silicon Dioxide (SiO2) - Chalcedony / Quartz aggregate) — sedimentary

Jasper with Agate and Quartz Inclusions

Silicon Dioxide (SiO2) - Chalcedony / Quartz aggregate

Quartzite river stone (Quartzite (SiO2)) — metamorphic

Quartzite river stone

Quartzite (SiO2)

Moss Agate (Silicon Dioxide with inclusions (SiO2)) — mineral

Moss Agate

Silicon Dioxide with inclusions (SiO2)

Moss Agate with Jasper (Chalcedony (SiO2 with inclusions)) — mineral

Moss Agate with Jasper

Chalcedony (SiO2 with inclusions)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide

Moss Agate (Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)) — mineral

Moss Agate

Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)

Sandstone Pebble (Arenite (primarily SiO2)) — sedimentary

Sandstone Pebble

Arenite (primarily SiO2)

Fossiliferous Limestone with Rugose Coral (Calcium Carbonate (CaCO3) featuring Rugosa (extinct order of solitary and colony corals)) — sedimentary

Fossiliferous Limestone with Rugose Coral

Calcium Carbonate (CaCO3) featuring Rugosa (extinct order of solitary and colony corals)

Coral Fossil (Agatized Coral or Petoskey Stone) (Hexagonaria percarinata (if Petoskey) or generally Scleractinia (Agatized Coral)) — Sedimentary/Fossil

Coral Fossil (Agatized Coral or Petoskey Stone)

Hexagonaria percarinata (if Petoskey) or generally Scleractinia (Agatized Coral)

Sedimentary/Fossil

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

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicon Dioxide (SiO2)) — fossil

Petrified Wood

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO₂)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (River Siltstone/Quartzite) (Sedimentary Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (River Siltstone/Quartzite)

Sedimentary Cryptocrystalline Quartz (SiO2)