Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

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

Chert (Hag Stone / Hole Stone) (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert (Hag Stone / Hole Stone)

Chert (Cryptocrystalline variety of Quartz, SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Chert (specifically Red Chert or Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Red Chert or Jasper)

Microcrystalline Quartz (SiO2)

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

Banded Chert (or Flint)

Microcrystalline Quartz (SiO2)

Chert (Brown variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Brown variety)

Silicon Dioxide (SiO2)

Fossiliferous Limestone (Crinoidal) (Calcium Carbonate (CaCO3) - Limestone containing bioclasts) — sedimentary

Fossiliferous Limestone (Crinoidal)

Calcium Carbonate (CaCO3) - Limestone containing bioclasts

Chert (Quartz Variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Quartz Variety)

Silicon Dioxide (SiO2)

Chert Pebble with Quartz Veining (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble with Quartz Veining

Microcrystalline Quartz (SiO2)

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

Banded Chert (River Siltstone)

Microcrystalline Quartz (SiO2)

Glauconitic Sandstone (Greensand) (Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone (Greensand)

Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)

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

Chert (Black Chert/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossiliferous Limestone (containing Brachiopods) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (containing Brachiopods)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Amber (Succinite) — Organic mineraloid

Amber

Succinite

Organic mineraloid

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Green Calcite (Calcium Carbonate (CaCO3)) — mineral

Green Calcite

Calcium Carbonate (CaCO3)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Ironstone Concretion (Limonite/Hematite Nodules) (Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)) — sedimentary

Ironstone Concretion (Limonite/Hematite Nodules)

Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)

Quartz Geode (Silicon Dioxide (SiO2) within a secondary sedimentary structure) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2) within a secondary sedimentary structure

Chert (Quartz Variety) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (Quartz Variety)

Microcrystalline Silica (SiO2)

Citrine (SiO2 (Silicon Dioxide)) — mineral

Citrine

SiO2 (Silicon Dioxide)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Graphite Schist (C (Carbonaceous Schist)) — metamorphic

Graphite Schist

C (Carbonaceous Schist)

Chert (Nodule / Geode fragment) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Nodule / Geode fragment)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified wood (principally Silicon Dioxide, SiO2)) — sedimentary

Petrified Wood

Silicified wood (principally Silicon Dioxide, SiO2)

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert (with Liesegang Banding) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (with Liesegang Banding)

Microcrystalline quartz (SiO2)

Anthracite Coal (Anthracite (Carbon-based organic sedimentary/metamorphic rock)) — metamorphic

Anthracite Coal

Anthracite (Carbon-based organic sedimentary/metamorphic rock)

Coal (Anthracite) (Anthracite (Carbon-based organic sedimentary/metamorphic rock)) — metamorphic

Coal (Anthracite)

Anthracite (Carbon-based organic sedimentary/metamorphic rock)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Quartz Geode (Silicon Dioxide (SiO2)) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2)

Green Jasper (with Quartz veining) (Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2) — sedimentary

Green Jasper (with Quartz veining)

Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2

Zebra Marble (Metamorphosed Alabaster/Limestone (CaCO3)) — metamorphic

Zebra Marble

Metamorphosed Alabaster/Limestone (CaCO3)

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Dalmatian Stone (commonly Dyed) (Dalmatian Jasper (Peralkaline igneous rock)) — igneous

Dalmatian Stone (commonly Dyed)

Dalmatian Jasper (Peralkaline igneous rock)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Coral Fossil (Petrified Coral) (Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)) — sedimentary

Coral Fossil (Petrified Coral)

Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)

Banded Chert (with Quartz Vein) (Microcrystalline Silica (SiO2)) — sedimentary

Banded Chert (with Quartz Vein)

Microcrystalline Silica (SiO2)

Massive Cryptocrystalline Quartz (Chert/Chalcedony Pebble) (Silicon Dioxide (SiO2)) — sedimentary

Massive Cryptocrystalline Quartz (Chert/Chalcedony Pebble)

Silicon Dioxide (SiO2)

Chert (specifically Iron-stained River Cobble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Iron-stained River Cobble)

Silicon Dioxide (SiO2)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Green Banded Chert (Agate/Jasper) (Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite) — sedimentary

Green Banded Chert (Agate/Jasper)

Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite