Rock Identifier

Category

Organic Gemstone

Browse organic gemstone specimens identified by the Rock Identifier community.

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

Chert Pebble

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Ferruginous Chert (Microcrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Ferruginous Chert

Microcrystalline Quartz (SiO2) with Iron Oxides

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

Chert (Black Chert/Flint) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Black Chert/Flint)

Cryptocrystalline Quartz (SiO2)

Fossilized Crinoid Stem Segment (Crinoid (Phylum Echinodermata, Class Crinoidea)) — sedimentary

Fossilized Crinoid Stem Segment

Crinoid (Phylum Echinodermata, Class Crinoidea)

Chert (specifically Flint or Common Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Common Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (containing Fossil Inclusions) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (containing Fossil Inclusions)

Microcrystalline Quartz (SiO2)

Fossiliferous Limestone (Coquina / Shell Limestone) (Biogenic Limestone (CaCO3)) — sedimentary

Fossiliferous Limestone (Coquina / Shell Limestone)

Biogenic Limestone (CaCO3)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO₂ / Silicon Dioxide)

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

Petrified Wood

Silicified Wood (SiO2 permineralization)

Amber (Succinite (fossilized resin)) — mineral

Amber

Succinite (fossilized resin)

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

Moss Agate

Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)

Black Marble (Recrystallized Calcite (CaCO3)) — metamorphic

Black Marble

Recrystallized Calcite (CaCO3)

Water and Silt (Sedimentary Environment) (Suspended Sediment / H2O (dihydrogen monoxide)) — sedimentary

Water and Silt (Sedimentary Environment)

Suspended Sediment / H2O (dihydrogen monoxide)

Amber (Fossilized Tree Resin (C10H16O)) — mineral

Amber

Fossilized Tree Resin (C10H16O)

Petrified Wood (Silicified Wood (SiO2)) — Mineral / Fossil

Petrified Wood

Silicified Wood (SiO2)

Mineral / Fossil

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

Peridot (Olivine)

Magnesium Iron Silicate (Mg, Fe)2SiO4

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — mineral

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (with Quartz vein) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (with Quartz vein)

Chert (Silicon Dioxide, SiO2)

Coquina (Biogenic Limestone (Calcium Carbonate - CaCO3)) — sedimentary

Coquina

Biogenic Limestone (Calcium Carbonate - CaCO3)

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

Chert (Jasper variety)

Microcrystalline Quartz (SiO2)

Brachiopod Fossil in Limestone (Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)) — sedimentary

Brachiopod Fossil in Limestone

Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)

Chert (Field Stone) (Microcrystalline / Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Field Stone)

Microcrystalline / Cryptocrystalline Quartz (SiO2)

Quartzite with inclusions (Quartzite) — metamorphic

Quartzite with inclusions

Quartzite

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Chert (with Limestone/Dolomite host) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Limestone/Dolomite host)

Microcrystalline Quartz (SiO2)

Moqui Marble (Shaman Stone) (Iron Oxide Concretion (composed primarily of Quartz sand with Hematite/Goethite shell)) — sedimentary

Moqui Marble (Shaman Stone)

Iron Oxide Concretion (composed primarily of Quartz sand with Hematite/Goethite shell)

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

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (with Quartz Vein) (Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)) — sedimentary

Chert (with Quartz Vein)

Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)

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

Chert (Pink Jasper variant)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Chert (Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Chalky variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Chalky variety)

Microcrystalline Quartz (SiO2)

Chert (and Limestone) River Cobble (Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)) — sedimentary

Chert (and Limestone) River Cobble

Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)

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

Chert / Jasper

Microcrystalline Quartz (SiO2)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Chert (and Jasper blend) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (and Jasper blend)

Chert (Microcrystalline Quartz, SiO2)

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

Chert (and/or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often called Flint or River Stone) (Chert (Microcrystalline Silicon Dioxide, SiO2)) — sedimentary

Chert (often called Flint or River Stone)

Chert (Microcrystalline Silicon Dioxide, SiO2)