Rock Identifier

Category

Organic Gemstone (Sedimentary Associations)

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

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

Chert Pebble

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Chert (often called Flint)

Chert (Microcrystalline Quartz, SiO2)

Fossiliferous Limestone (Coquina) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (Coquina)

Biogenic Limestone (Calcium Carbonate, CaCO3)

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Flint)

Silicon Dioxide (SiO2)

Fossiliferous Limestone (Coquina / Shell Limestone) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (Coquina / Shell Limestone)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Chert (with Iron Staining) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (with Iron Staining)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood) (Silicified Paleoflora (mainly Quartz, SiO2)) — metamorphic

Petrified Wood (Silicified Wood)

Silicified Paleoflora (mainly Quartz, SiO2)

Limestone (Weathered) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Weathered)

Calcium Carbonate (CaCO3)

Ironstone Concretion / Hematite Nodules (Ferruginous Sedimentary Rock (primarily Hematite Fe2O3 and Goethite FeO(OH))) — sedimentary

Ironstone Concretion / Hematite Nodules

Ferruginous Sedimentary Rock (primarily Hematite Fe2O3 and Goethite FeO(OH))

Chert (and Limestone) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and Limestone)

Silicon Dioxide (SiO2)

Chert (White-Tan variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White-Tan variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sandstone (Arenicola (comprising mostly Quartz, SiO2)) — sedimentary

Sandstone

Arenicola (comprising mostly Quartz, SiO2)

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

Chert (Green variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper (specifically Polychrome or Desert Jasper) (Silicon Dioxide (SiO2) with iron oxide and other mineral impurities) — sedimentary (chemical/biological origin)

Jasper (specifically Polychrome or Desert Jasper)

Silicon Dioxide (SiO2) with iron oxide and other mineral impurities

sedimentary (chemical/biological origin)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Green Quartz (Prasiolite/Adventurine) (Silicon Dioxide with inclusions (SiO2)) — mineral

Green Quartz (Prasiolite/Adventurine)

Silicon Dioxide with inclusions (SiO2)

Citrine (SiO2 (Silicon Dioxide)) — mineral

Citrine

SiO2 (Silicon Dioxide)

Greisen (Quartz-Muscovite-Turretine Rock) (Greisen) — Metamorphic Rock

Greisen (Quartz-Muscovite-Turretine Rock)

Greisen

Metamorphic Rock

Turquoise (Turquoise, CuAl6(PO4)4(OH)8·4H2O) — mineral

Turquoise

Turquoise, CuAl6(PO4)4(OH)8·4H2O

Crushed Limestone (Calcite-rich Sedimentary Rock (CaCO3)) — sedimentary

Crushed Limestone

Calcite-rich Sedimentary Rock (CaCO3)

Ferruginous Sandstone (Ironstone) (Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)) — sedimentary

Ferruginous Sandstone (Ironstone)

Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)

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

Moss Agate

Silicon Dioxide with inclusions (SiO2 + impurities)

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

Chert (Field Stone)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Tan/Grey variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Tan/Grey variety)

Silicon Dioxide (SiO2)

Chert (often called Flint or Jasper locally) (Chert (Microcrystalline Quartz, Formula: SiO2)) — sedimentary

Chert (often called Flint or Jasper locally)

Chert (Microcrystalline Quartz, Formula: SiO2)

Mother of Pearl (Nacre) (Aragonite (CaCO3) with Organic Matrix) — mineral

Mother of Pearl (Nacre)

Aragonite (CaCO3) with Organic Matrix

Hematite (Hematite (Fe2O3)) — mineral

Hematite

Hematite (Fe2O3)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

Chert (Jasper/Iron-stained Quartzite) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Iron-stained Quartzite)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert (Nodule/Pebble) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Nodule/Pebble)

Chert (Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossilized Shark Tooth (Fossilized elasmobranch tooth (Apatite/Calcium Phosphate)) — sedimentary

Fossilized Shark Tooth

Fossilized elasmobranch tooth (Apatite/Calcium Phosphate)

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

Petrified Wood

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

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

Chert (specifically Flint or Common Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Iron-stained or Jasperoid Chert) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Iron-stained or Jasperoid Chert)

Microcrystalline Quartz (SiO2)

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

Chert / Flint Nodules

Cryptocrystalline Quartz (SiO2)

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

Chert (Yellow Jasper/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Nodule)

Microcrystalline Quartz (SiO2)

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

Chert (Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)