Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

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

Learn about Organic Gemstone (Sedimentary Classification) in the encyclopedia

Sapropel

Bituminous Shale

Bituminous Shale

Black Shale

Red Garnet

Conglomerate

Quartzite Sandstone

Quartzite Sandstone

Breccia

Ironstone

Oil Shale

Jet

Petrified Wood

Amber

Banded Chert (Cryptocrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Cryptocrystalline Quartz (SiO2)

Pearl jewelry (Pearl (biogenic calcium carbonate, primarily aragonite, CaCO₃)) — gemstone

Pearl jewelry

Pearl (biogenic calcium carbonate, primarily aragonite, CaCO₃)

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

Petrified Wood

Silicified Wood (primarily Quartz / Chalcedony: SiO2)

Limestone (Sedimentary Rock (Primarily CaCO3)) — sedimentary

Limestone

Sedimentary Rock (Primarily CaCO3)

Fossiliferous Limestone (Calcium Carbonate (CaCO3) with marine fossils) — fossil

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with marine fossils

Limestone with Fossil Fragments (Bioclastic Carbonate Rock (CaCO3)) — sedimentary

Limestone with Fossil Fragments

Bioclastic Carbonate Rock (CaCO3)

Pearl (Calcium Carbonate (Aragonite/Calcite) with Conchiolin (CaCO3)) — mineral

Pearl

Calcium Carbonate (Aragonite/Calcite) with Conchiolin (CaCO3)

Coal (Bituminous or Anthracite) (Carbonaceous sedimentary rock (primarily Carbon, C)) — sedimentary

Coal (Bituminous or Anthracite)

Carbonaceous sedimentary rock (primarily Carbon, C)

Gravel / Limestone Fragment (Calcium Carbonate (CaCO3) / Fine-grained Sedimentary Rock) — sedimentary

Gravel / Limestone Fragment

Calcium Carbonate (CaCO3) / Fine-grained Sedimentary Rock

White seed-bead gemstone strand, likely freshwater pearl or shell pearl (Pearl: nacreous calcium carbonate, chiefly aragonite (CaCO₃) in conchiolin; identification uncertain from image) — gemstone

White seed-bead gemstone strand, likely freshwater pearl or shell pearl

Pearl: nacreous calcium carbonate, chiefly aragonite (CaCO₃) in conchiolin; identification uncertain from image

Black Freshwater Pearls (Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3) — mineral

Black Freshwater Pearls

Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide

Travertine (Travertine (a terrestrial form of Limestone, CaCO3)) — sedimentary

Travertine

Travertine (a terrestrial form of Limestone, CaCO3)

Tumbled brown agate (likely moss or plume agate) (Microcrystalline quartz, chiefly chalcedony (SiO₂), with iron-oxide and possibly mineral inclusions) — gemstone

Tumbled brown agate (likely moss or plume agate)

Microcrystalline quartz, chiefly chalcedony (SiO₂), with iron-oxide and possibly mineral inclusions

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

Ferruginous Sandstone with Concretion

Sandstone (SiO2 dominated with Fe2O3 cement)

Pearl and Garnet Glass (Calcium Carbonate (CaCO3) for pearl; Silicon Dioxide (SiO2) for glass) — mineral and glass

Pearl and Garnet Glass

Calcium Carbonate (CaCO3) for pearl; Silicon Dioxide (SiO2) for glass

mineral and glass

Chert with Quartz Veins (Microcrystalline silica (SiO2)) — sedimentary

Chert with Quartz Veins

Microcrystalline silica (SiO2)

Amber (Succinite (Fossilized Tree Resin)) — gemstone

Amber

Succinite (Fossilized Tree Resin)

Polished amber-colored translucent stone, likely citrine or yellow chalcedony (Most consistent with quartz (SiO₂), potentially citrine; translucent yellow chalcedony is another possibility) — mineral

Polished amber-colored translucent stone, likely citrine or yellow chalcedony

Most consistent with quartz (SiO₂), potentially citrine; translucent yellow chalcedony is another possibility

Petrified Wood (Silicified Wood (SiO2 - Quartz/Chalcendony replacing organic matter)) — sedimentary

Petrified Wood

Silicified Wood (SiO2 - Quartz/Chalcendony replacing organic matter)

Limestone with Gastropod Fossil (Sedimentary Calcium Carbonate (CaCO3) with Gastropoda inclusion) — fossil

Limestone with Gastropod Fossil

Sedimentary Calcium Carbonate (CaCO3) with Gastropoda inclusion

Amber (Succinite (C10H16O)) — mineral

Amber

Succinite (C10H16O)

Limestone Pebble (Sedimentary carbonate rock (CaCO3)) — sedimentary

Limestone Pebble

Sedimentary carbonate rock (CaCO3)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Geode (Unopened) (Silica-rich concretion (SiO2)) — sedimentary

Geode (Unopened)

Silica-rich concretion (SiO2)

Amber (Succinite (C10H16O)) — mineraloid

Amber

Succinite (C10H16O)

Amber (Succinite (C10H16O)) — mineraloid

Amber

Succinite (C10H16O)

Moss Agate (Chalcedony (Silicon Dioxide, SiO2) with inclusions of Chlorite, Manganese, or Iron) — mineral

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions of Chlorite, Manganese, or Iron

Coal (Anthracite / Bituminous Coal) — sedimentary

Coal

Anthracite / Bituminous Coal

Chert (Yellow Jasper/Honey Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Jasper/Honey Chert)

Silicon Dioxide (SiO2)

Pearl (likely Freshwater or Akoya Cultured) (Aragonite / Conchiolin composite (CaCO3)) — Mineralloid (Organic gemstone)

Pearl (likely Freshwater or Akoya Cultured)

Aragonite / Conchiolin composite (CaCO3)

Mineralloid (Organic gemstone)

Knightia Fossil in Limestone (Knightia eocaena in micritic limestone) — sedimentary

Knightia Fossil in Limestone

Knightia eocaena in micritic limestone

Fossiliferous Limestone (Fossiliferous Limestone (CaCO3)) — sedimentary

Fossiliferous Limestone

Fossiliferous Limestone (CaCO3)

Fossiliferous Limestone (Calcite (CaCO3) matrix with biogenic fragments) — sedimentary

Fossiliferous Limestone

Calcite (CaCO3) matrix with biogenic fragments

Fossiliferous Limestone (Fossiliferous Limestone (containing bioclasts)) — sedimentary

Fossiliferous Limestone

Fossiliferous Limestone (containing bioclasts)

Banded Limestone (Calcareous sedimentary rock (CaCO3)) — sedimentary

Banded Limestone

Calcareous sedimentary rock (CaCO3)

Jasper / Agate with Petrified Wood Inclusion (SiO2) — mineral

Jasper / Agate with Petrified Wood Inclusion

SiO2

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

Chert (White Chert)

Silicon Dioxide (SiO2)

Jasper (Microcrystalline Quartz (SiO2)) — Sedimentary/Mineral

Jasper

Microcrystalline Quartz (SiO2)

Sedimentary/Mineral

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Poppy Jasper (Microcrystalline Quartz (SiO2) with mineral inclusions) — sedimentary

Poppy Jasper

Microcrystalline Quartz (SiO2) with mineral inclusions

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)