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

Amber (Succinite) — mineraloid

Amber

Succinite

Liesegang Ring Siltstone (Siltstone with iron oxide Liesegang bands) — sedimentary

Liesegang Ring Siltstone

Siltstone with iron oxide Liesegang bands

Moss Agate with Quartz Druzy (Chalcedony with inclusions (SiO2)) — mineral

Moss Agate with Quartz Druzy

Chalcedony with inclusions (SiO2)

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

Moss Agate

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

Yellow Sapphire or Citrine (Al2O3 (Corundum) or SiO2 (Quartz)) — mineral

Yellow Sapphire or Citrine

Al2O3 (Corundum) or SiO2 (Quartz)

Chert (River Pebble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (River Pebble)

Silicon Dioxide (SiO2)

Dinosaur Bone (Gembone) (Agatized Dinosaur Bone (Silicified Paleo-osteoid)) — metamorphic

Dinosaur Bone (Gembone)

Agatized Dinosaur Bone (Silicified Paleo-osteoid)

Fossil Coral (Honeycomb Coral) (Favosites (extinct genus of Tabulate coral)) — sedimentary

Fossil Coral (Honeycomb Coral)

Favosites (extinct genus of Tabulate coral)

Chert (Gravel pebble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Gravel pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Amber (Amber (C10H16O)) — mineral

Amber

Amber (C10H16O)

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

Chert

Chert (Microcrystalline Quartz, SiO2)

Fossil Shark Tooth (Lamniform (Mackerel Shark) fossil tooth, likely Otodus or Cretalamna) — fossil

Fossil Shark Tooth

Lamniform (Mackerel Shark) fossil tooth, likely Otodus or Cretalamna

Sandstone with Fossil Leaf Impression (Sedimentary rock (Sandstone/Siltstone matrix) with Carbonaceous film fossil) — fossil

Sandstone with Fossil Leaf Impression

Sedimentary rock (Sandstone/Siltstone matrix) with Carbonaceous film fossil

Chert (or Fossiliferous Limestone) (Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)) — sedimentary

Chert (or Fossiliferous Limestone)

Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)

Chert (varieties include Flint and Jasper) (Silicon dioxide (SiO2)) — sedimentary

Chert (varieties include Flint and Jasper)

Silicon dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

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

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

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

Jasper

Jasper (Silicon Dioxide, SiO2)

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

Chert / River Jasper

Silicon Dioxide (SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

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

Chert / Flint

Silicon Dioxide (SiO2)

Chert (often called Jasper or River Rock) (Chert (SiO2)) — sedimentary

Chert (often called Jasper or River Rock)

Chert (SiO2)

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

Petrified Wood

Silicified Wood (primarily Chalcedony or Quartz, SiO2)

Chert (Flint) (Chert (̑SiO2)) — sedimentary

Chert (Flint)

Chert (̑SiO2)

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

Chert (Jasper)

Microcrystalline Quartz (SiO2)

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

Chert (Yellow Jasper/Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Yellow Chert (Jasper)

Silicon Dioxide (SiO2)

Geode (Unopened) (SiO2 (Quartz-filled Sedimentary Nodule)) — sedimentary

Geode (Unopened)

SiO2 (Quartz-filled Sedimentary Nodule)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

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

Red Chert (Jasper)

Microcrystalline Quartz (SiO2)

Ironstone Concretion (Goethite-rich Siltstone / Siderite (FeCO3)) — sedimentary

Ironstone Concretion

Goethite-rich Siltstone / Siderite (FeCO3)

Agatized Fossil or Chalcedony Nodule (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Agatized Fossil or Chalcedony Nodule

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chert (varieties include Flint and Jasper) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (varieties include Flint and Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossilized Shark Tooth (Elasmobranchii fossil (likely Odontaspididae family)) — sedimentary

Fossilized Shark Tooth

Elasmobranchii fossil (likely Odontaspididae family)

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

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

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

Chert (Pebble)

Microcrystalline silica (SiO2)

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

Chert (and Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pyrite (Iron Disulfide (FeS2)) — mineral

Pyrite

Iron Disulfide (FeS2)

Petrified Wood (Calamites Fossil) (Calamites sp. (Silicified/Permineralized Plant Fossil)) — sedimentary

Petrified Wood (Calamites Fossil)

Calamites sp. (Silicified/Permineralized Plant Fossil)

Chert (Sedimentary Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert

Sedimentary Cryptocrystalline Quartz (SiO2)