Rock Identifier

Category

Fossil

Browse fossil specimens identified by the Rock Identifier community.

Limestone with Chert or Siltstone bands (Sedimentary carbonate rock (CaCO3) often with siliceous impurities) — sedimentary

Limestone with Chert or Siltstone bands

Sedimentary carbonate rock (CaCO3) often with siliceous impurities

Limestone (Calcium carbonate (CaCO3)) — sedimentary

Limestone

Calcium carbonate (CaCO3)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

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

Sandstone (likely Fossiliferous Sandstone)

Clastic sedimentary rock (primarily SiO2)

Chalk (Limestone variant) (Calcium Carbonate (CaCO3)) — sedimentary

Chalk (Limestone variant)

Calcium Carbonate (CaCO3)

Shale (Fissile mudstone (Shale)) — sedimentary

Shale

Fissile mudstone (Shale)

Anthracite Coal (Anthracite (high-rank coal / Carbon)) — metamorphic

Anthracite Coal

Anthracite (high-rank coal / Carbon)

Coal (most likely Bituminous or Anthracite) (Coal (organic sedimentary rock)) — Sedimentary

Coal (most likely Bituminous or Anthracite)

Coal (organic sedimentary rock)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

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

Chert

Chert (Microcrystalline Quartz, SiO2)

Milky Quartz with Dendritic Inclusions (Silicon Dioxide (SiO2)) — mineral

Milky Quartz with Dendritic Inclusions

Silicon Dioxide (SiO2)

Red Shale (Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)) — sedimentary

Red Shale

Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)

Sandstone with Ironstone Concretion (Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))) — sedimentary

Sandstone with Ironstone Concretion

Arenite with Hematite/Goethite nodules (Fe2O3 / FeO(OH))

Red Sandstone (Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)) — sedimentary

Red Sandstone

Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Sandstone (with Iron Staining) (Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)) — sedimentary

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Ammonite Fossil (Polished Section) (Ammonoidea (typically mineralized with Calcite CaCO3)) — sedimentary

Ammonite Fossil (Polished Section)

Ammonoidea (typically mineralized with Calcite CaCO3)

Amber (Succinite) — Organic (Mineraloid)

Amber

Succinite

Organic (Mineraloid)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Quartzite River Rock with Dendrites (Metamorphosed Quartz-rich Sandstone with Manganese Oxide (MnO2) inclusions) — metamorphic

Quartzite River Rock with Dendrites

Metamorphosed Quartz-rich Sandstone with Manganese Oxide (MnO2) inclusions

Ironstone concretion / Limonitic Sandstone (Goethite/Hematite Cemented Sandstone (Hydrated Iron Oxide)) — sedimentary

Ironstone concretion / Limonitic Sandstone

Goethite/Hematite Cemented Sandstone (Hydrated Iron Oxide)

Sandstone (with Concretion) (Arenite / Quartzose Sandstone) — sedimentary

Sandstone (with Concretion)

Arenite / Quartzose Sandstone

Dendritic Agate (Chalcedony (SiO2) with manganese/iron oxide inclusions) — mineral

Dendritic Agate

Chalcedony (SiO2) with manganese/iron oxide inclusions

Stromatolite (Biogenic Sedimentary Rock (composed predominantly of CaCO3)) — sedimentary

Stromatolite

Biogenic Sedimentary Rock (composed predominantly of CaCO3)

Limestone (Buff/Tan) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Buff/Tan)

Calcium Carbonate (CaCO3)

Sandstone (Ferruginous) (Arenite (SiO2 with Iron Oxide impurities)) — sedimentary

Sandstone (Ferruginous)

Arenite (SiO2 with Iron Oxide impurities)

Sandstone Concretion (Clastic Sedimentary Concretion (typically Quartz/Silica with Iron Oxide)) — sedimentary

Sandstone Concretion

Clastic Sedimentary Concretion (typically Quartz/Silica with Iron Oxide)

Siltstone (Siltstone (fined-grained clastic sedimentary rock)) — sedimentary

Siltstone

Siltstone (fined-grained clastic sedimentary rock)

Sandstone (Weathered Cobble) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Weathered Cobble)

Clastic Sedimentary Rock (primarily 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)

Limonite Concretion (Limonite (Hydrated Iron Oxide) FeO(OH)·nH2O) — sedimentary

Limonite Concretion

Limonite (Hydrated Iron Oxide) FeO(OH)·nH2O

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

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sandstone (Quartzose Sandstone) (Arenite) — sedimentary

Sandstone (Quartzose Sandstone)

Arenite

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Sandstone (Quartzose Sandstone) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartzose Sandstone)

Arenite (primarily SiO2)

Red Sandstone (Clastic Terrigenous Sedimentary Rock (typically Hematitic Quartz Arenite or Arkose)) — sedimentary

Red Sandstone

Clastic Terrigenous Sedimentary Rock (typically Hematitic Quartz Arenite or Arkose)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Botryoidal Chalcedony (Silicon Dioxide (SiO2)) — mineral

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Sandstone (Red) (Arenite (SiO2 with Fe2O3)) — sedimentary

Sandstone (Red)

Arenite (SiO2 with Fe2O3)

Sandstone (Quartzose Sandstone) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (primarily SiO2)