Rock Identifier

Category

Organic Gemstone (Often Associated With Sedimentary Sequences)

Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.

Chert (often called Flint when dark) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossilized Megalodon Tooth Fragment (Otodus megalodon (Carcharocles megalodon fossil)) — sedimentary

Fossilized Megalodon Tooth Fragment

Otodus megalodon (Carcharocles megalodon fossil)

Nobby Hematite (Iron Ore) (Hematite (Fe2O3)) — mineral

Nobby Hematite (Iron Ore)

Hematite (Fe2O3)

Fossiliferous Limestone (Bioclastic Limestone (composition: CaCO3)) — sedimentary

Fossiliferous Limestone

Bioclastic Limestone (composition: CaCO3)

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

Chert (Nodule)

Chert (Silicon Dioxide, SiO2)

Fossil Coral (Rugose Coral Fragment) (Rugosa (extinct order of solitary and colonial corals)) — sedimentary

Fossil Coral (Rugose Coral Fragment)

Rugosa (extinct order of solitary and colonial corals)

Chert (often called Jasper in this color variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (often called Jasper in this color variety)

Microcrystalline Quartz (SiO2)

Chert (variously known as Flint or Jasper) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (variously known as Flint or Jasper)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Green Calcite (Calcite (CaCO3)) — mineral

Green Calcite

Calcite (CaCO3)

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

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

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

Chert (often called Flint)

Chert (Microcrystalline Quartz, SiO2)

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

Chert (Iron-stained)

Chert (primarily Microcrystalline Quartz, SiO2)

Chert (Jasper/Flint variety) (Microcrystalline silicon dioxide (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline silicon dioxide (SiO2)

Fluorite with Rhodochrosite (Fluorite (CaF2) and Rhodochrosite (MnCO3)) — Mineral

Fluorite with Rhodochrosite

Fluorite (CaF2) and Rhodochrosite (MnCO3)

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

Chert Pebble (Flint)

Microcrystalline/Cryptocrystalline Quartz (SiO2)

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

Chert (Flint/Jasper variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicon Dioxide (SiO2) - Calcified / Silicified Wood) — sedimentary

Petrified Wood

Silicon Dioxide (SiO2) - Calcified / Silicified Wood

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

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

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

Banded Chert (or Flint)

Microcrystalline Quartz (SiO2)

Banded Chert (River Siltstone) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert (River Siltstone)

Microcrystalline Quartz (SiO2)

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

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Graphite Schist (C (Carbonaceous Schist)) — metamorphic

Graphite Schist

C (Carbonaceous Schist)

Chert (specifically Chalcedony/Flint variant) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Chalcedony/Flint variant)

Silicon Dioxide (SiO2)

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

Chert (Beach Pebble)

Microcrystalline Quartz (SiO2)

Orange Calcite (Mexican Onyx) (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite (Mexican Onyx)

Calcium Carbonate (CaCO3)

Common Opal (Green Opal / Pistachio Opal) (Hydrated silica (SiO2·nH2O)) — mineraloid

Common Opal (Green Opal / Pistachio Opal)

Hydrated silica (SiO2·nH2O)

Bituminous Coal (Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)) — sedimentary

Bituminous Coal

Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)

Chert (variant Flint/Jasper) (Microcrystalline Opaline Silica (SiO2)) — sedimentary

Chert (variant Flint/Jasper)

Microcrystalline Opaline Silica (SiO2)

Native Copper (Native Copper (Cu)) — mineral

Native Copper

Native Copper (Cu)

Anthracite Coal (Anthracite (Carbon-rich metamorphic coal)) — metamorphic

Anthracite Coal

Anthracite (Carbon-rich metamorphic coal)

Conglomerate (Conglomerate (clastic sedimentary rock)) — sedimentary

Conglomerate

Conglomerate (clastic sedimentary rock)

Larimar (Pectolite (a variety of pectolite, NaCa2Si3O8(OH))) — Mineral

Larimar

Pectolite (a variety of pectolite, NaCa2Si3O8(OH))

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

Chert (specifically Yellow/Brown Chert or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Black Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

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

Chert (Black Flint)

Silicon Dioxide (SiO2)

Red Sandstone (Ferruginous Sandstone (SiO2 dominated with Fe2O3 cement)) — sedimentary

Red Sandstone

Ferruginous Sandstone (SiO2 dominated with Fe2O3 cement)

Red Sandstone (Arenite (Ferruginous Sandstone)) — sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

Chert (specifically Green Chert/Jasper) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (specifically Green Chert/Jasper)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Biotite Schist (Biotite Schist) — metamorphic

Biotite Schist

Biotite Schist

Rough Garnet (Almandine) (Almandine Garnet (Fe3Al2(SiO4)3)) — mineral

Rough Garnet (Almandine)

Almandine Garnet (Fe3Al2(SiO4)3)

Pearl (Aragonite (CaCO3 with conchiolin)) — mineral

Pearl

Aragonite (CaCO3 with conchiolin)