Rock Identifier

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Organic Gemstone (Biogenic)

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

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Jet

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

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

sedimentary
Jasper (Silicon Dioxide (SiO2)) — sedimentary

Jasper

Silicon Dioxide (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Chert / Flint

Silicon Dioxide (SiO2) - Microcrystalline Quartz

sedimentary
Chert (Jasper variety) (Silicon Dioxide (SiO2) with iron oxide impurities) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2) with iron oxide impurities

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

Petrified Wood

Silicified Wood (SiO2)

fossil
Chert (often called Flint when found in chalk) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint when found in chalk)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline Silicon Dioxide (SiO2)

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

Chert (Jasper)

Microcrystalline Quartz (SiO2)

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

Jasper (Red Jasper)

Silicon Dioxide (SiO₂)

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

Chert (Nodule)

Microcrystalline Quartz (SiO2)

sedimentary
Pearl (Calcium Carbonate (Aragonite/Calcite) with Conchiolin (CaCO3)) — mineral

Pearl

Calcium Carbonate (Aragonite/Calcite) with Conchiolin (CaCO3)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

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

Petrified Wood

Silicified wood (principally SiO2)

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

Moss Agate

Silicon Dioxide (SiO2) with inclusions

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

Chert / Flint

Silicon Dioxide (SiO2)

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

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

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

Chert (Black Chert/Flint)

Silicon Dioxide (SiO2)

sedimentary
Fancy Jasper (Jasper (Cryptocrystalline Quartz, SiO2)) — sedimentary

Fancy Jasper

Jasper (Cryptocrystalline Quartz, SiO2)

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

Chert (Yellow Jasper/Flint)

Silicon Dioxide (SiO2)

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

Chert (Black Chert/Flint)

Silicon Dioxide (SiO2)

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

Chert (specifically Flint)

Silicon Dioxide (SiO2)

sedimentary
Black Jasper (Silicon Dioxide (SiO2) with impurities) — sedimentary

Black Jasper

Silicon Dioxide (SiO2) with impurities

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

Chert (Jasper)

Cryptocrystalline Quartz (SiO2)

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

Chert (Red Jasper variant)

Microcrystalline Quartz (SiO2)

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

Chert (Jasper)

Microcrystalline Quartz (SiO2)

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

Chert (often called Flint)

Microcrystalline Quartz (SiO2)

sedimentary
Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

sedimentary
Chalcedony (Cryptocrystalline Quartz (SiO2)) — mineral

Chalcedony

Cryptocrystalline Quartz (SiO2)

mineral
Amber (Succinite (C10H16O)) — mineraloid

Amber

Succinite (C10H16O)

mineraloid
Moss Agate (Chalcedony (Silicon Dioxide, SiO2) with inclusions of Chlorite, Manganese, or Iron) — mineral

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions of Chlorite, Manganese, or Iron

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

Petrified Wood

Silicified Wood (primarily SiO2)

mineral
Red Chert (Jasper) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Red Chert (Jasper)

Silicon Dioxide (SiO2) with iron oxide inclusions

sedimentary
Amber (Succinite (organic mineraloid); Chemical formula: C10H16O) — mineral

Amber

Succinite (organic mineraloid); Chemical formula: C10H16O

mineral
Green Moss Agate (Silicon Dioxide (SiO2) with Mineral Inclusions) — sedimentary

Green Moss Agate

Silicon Dioxide (SiO2) with Mineral Inclusions

sedimentary
Fossil bivalve shell (Likely an extinct or modern-like ribbed cockle/scallop; exact genus requires locality and diagnostic hinge features) — fossil

Fossil bivalve shell

Likely an extinct or modern-like ribbed cockle/scallop; exact genus requires locality and diagnostic hinge features

fossil
Pink Opal (Amorphous Hydrous Silica (SiO2·nH2O)) — mineral

Pink Opal

Amorphous Hydrous Silica (SiO2·nH2O)

mineral
Likely weathered flint or chert fragment (Cryptocrystalline quartz (SiO₂), possibly siliceous chert/flint) — sedimentary

Likely weathered flint or chert fragment

Cryptocrystalline quartz (SiO₂), possibly siliceous chert/flint

sedimentary
Jasper (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper

Silicon Dioxide (SiO2) with impurities

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

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

sedimentary
Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

sedimentary