Rock Identifier

Category

Organic Gemstone

Browse organic gemstone specimens identified by the Rock Identifier community.

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

Chert (and Flint variant)

Microcrystalline Quartz (SiO2)

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

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

Chert (Jasper type)

Microcrystalline Quartz (SiO2)

Chert (Yellow/Tan variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow/Tan variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Chert (Chert Nodule with Chalky Cortex) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Chert Nodule with Chalky Cortex)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (often called Flint) (Chert (Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (often called Flint)

Chert (Cryptocrystalline Quartz, SiO2)

Chert (Basanite / Flint) (Microcrystalline silica (SiO2)) — sedimentary

Chert (Basanite / Flint)

Microcrystalline silica (SiO2)

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

Chert (often called Flint)

Cryptocrystalline Quartz (SiO2)

Mosasaur Tooth Fossil (Mosasaurid vertebrate fossil (Hydroxyapatite)) — mineral

Mosasaur Tooth Fossil

Mosasaurid vertebrate fossil (Hydroxyapatite)

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

Chert (variations include Flint)

Chert (Silicon Dioxide, SiO2)

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Ironstone Concretion / Limonite Node (Goethite and Limonite (FeO(OH) nH2O)) — sedimentary

Ironstone Concretion / Limonite Node

Goethite and Limonite (FeO(OH) nH2O)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Green Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Green Chert

Microcrystalline Quartz (SiO2)

Sandstone (likely Fossiliferous Sandstone) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (likely Fossiliferous Sandstone)

Clastic sedimentary rock (primarily SiO2)

Chert with Quartz Veining (Silicon Dioxide (SiO2)) — sedimentary

Chert with Quartz Veining

Silicon Dioxide (SiO2)

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

Chert (often called Flint)

Chert (SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Chert (Fossiliferous) (Silicon dioxide (SiO2)) — sedimentary

Chert (Fossiliferous)

Silicon dioxide (SiO2)

Chert (often found as Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often found as Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Basanite / Flint variety)

Microcrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Chert (Beach Pebble)

Microcrystalline Quartz (SiO2)

Fossilized Coral (Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)) — sedimentary

Fossilized Coral

Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)

Chert (specifically as a lithic artifact/projectile point) (Chert (Silicon dioxide, SiO2)) — sedimentary

Chert (specifically as a lithic artifact/projectile point)

Chert (Silicon dioxide, SiO2)

Chert (Iron-stained) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline quartz (SiO2)

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

Chert (Yellow Jasper/Flint)

Microcrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily Chalcedony or Quartz, SiO2)

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

Chert (Nodule)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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)

Citrine (Silicon Dioxide (SiO2) with iron impurities) — mineral

Citrine

Silicon Dioxide (SiO2) with iron impurities

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

Petrified Wood

Silicified Wood (primarily SiO₂ - Silicon Dioxide)

Peridot (Olivine (Mg, Fe)2SiO4) — mineral

Peridot

Olivine (Mg, Fe)2SiO4

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)) — mineral

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

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

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

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

Chert (Flint)

Silicon Dioxide (SiO2)