Rock Identifier

Category

Fossil

Browse fossil specimens identified by the Rock Identifier community.

Learn about Fossil in the encyclopedia

Fossil Opal

Fossil Opal

Amber

Amber

Bone Opal

Bone Opal

Turritella Jasper

Turritella Jasper

Fossiliferous Limestone

Fossiliferous Limestone

Turritella Agate

Turritella Agate

Petrified Wood

Petrified Wood

Diatomite

Diatomite

Guano

Guano

Jet

Jet

Diatomaceous Earth

Diatomaceous Earth

Opalized Wood

Opalized Wood

Siltstone (Siltstone (primarily composed of microcrystalline Quartz and Feldspar)) — sedimentary

Siltstone

Siltstone (primarily composed of microcrystalline Quartz and Feldspar)

Shale (with minor calcite veining) (Clastic sedimentary rock (primarily clay minerals and quartz)) — sedimentary

Shale (with minor calcite veining)

Clastic sedimentary rock (primarily clay minerals and quartz)

Siltstone (Siltstone) — sedimentary

Siltstone

Siltstone

Chert (or Fossiliferous Limestone) (Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)) — sedimentary

Chert (or Fossiliferous Limestone)

Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)

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

Chert (Chert Nodule with Cortex)

Microcrystalline Quartz (SiO2)

Ironstone Concretion (Limonite/Goethite) (Ferruginous Sandstone / Ironstone (FeO(OH)·nH2O)) — sedimentary

Ironstone Concretion (Limonite/Goethite)

Ferruginous Sandstone / Ironstone (FeO(OH)·nH2O)

Asphalt Concrete (Bituminous Concrete (Anthropic Rock)) — sedimentary

Asphalt Concrete

Bituminous Concrete (Anthropic Rock)

Sandstone (Ferruginous) (Arenite (Fe-rich SiO2)) — sedimentary

Sandstone (Ferruginous)

Arenite (Fe-rich SiO2)

Limestone (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Chert pebble (Microcrystalline silica (SiO2)) — sedimentary

Chert pebble

Microcrystalline silica (SiO2)

Sandstone (Ferruginous) (Arenite (with Iron Oxide cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (with Iron Oxide cement)

Sandstone (Ferruginous) (Arenite (with Iron Oxides)) — sedimentary

Sandstone (Ferruginous)

Arenite (with Iron Oxides)

Fossilized Brachiopod (Phylum Brachiopoda (General mineral composition: Calcite/CaCO₃ or Silica/SiO₂)) — sedimentary

Fossilized Brachiopod

Phylum Brachiopoda (General mineral composition: Calcite/CaCO₃ or Silica/SiO₂)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Chert Nodule (Commonly known as a Flint or River Cobble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert Nodule (Commonly known as a Flint or River Cobble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sandstone (likely Calcareous or Quartz-rich) (Arenite (SiO2 based typically)) — sedimentary

Sandstone (likely Calcareous or Quartz-rich)

Arenite (SiO2 based typically)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Red Mudstone (Siltstone) (Lutite (primarily Quartz and Clay minerals with Hematite)) — sedimentary

Red Mudstone (Siltstone)

Lutite (primarily Quartz and Clay minerals with Hematite)

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

Chert (Nodule)

Chert (Silicon Dioxide, SiO2)

Sandstone Cobble (Arenite (Secondary classification based on grain size)) — sedimentary

Sandstone Cobble

Arenite (Secondary classification based on grain size)

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

Sandstone (Ferruginous)

Arenite (with Iron Oxide)

Limestone (CaCO3 (principally composed of Calcite)) — sedimentary

Limestone

CaCO3 (principally composed of Calcite)

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Chert Nodules (Limonitic Chert) (Cryptocrystalline Quartz (SiO2) with Hydrated Iron Oxides) — sedimentary

Chert Nodules (Limonitic Chert)

Cryptocrystalline Quartz (SiO2) with Hydrated Iron Oxides

Ferruginous Sandstone (with Laterite) (Ferruginous Arenite (FeO(OH)·nH2O)) — sedimentary

Ferruginous Sandstone (with Laterite)

Ferruginous Arenite (FeO(OH)·nH2O)

Coal (likely Bituminous or Lignite) (Organic Sedimentary Rock (Carbonaceous)) — sedimentary

Coal (likely Bituminous or Lignite)

Organic Sedimentary Rock (Carbonaceous)

Lignite (Brown Coal) (Humic Lignite (Carbonaceous sedimentary rock)) — sedimentary

Lignite (Brown Coal)

Humic Lignite (Carbonaceous sedimentary rock)

Sandstone Pebble (Arenite (primarily SiO2)) — sedimentary

Sandstone Pebble

Arenite (primarily SiO2)

Sandstone (Greywacke) (Arenite / Greywacke Sandstone) — sedimentary

Sandstone (Greywacke)

Arenite / Greywacke Sandstone

Pyrite (Iron Disulfide (FeS2)) — mineral

Pyrite

Iron Disulfide (FeS2)

Siltstone (Siltstone (primarily SiO2 with clay minerals)) — sedimentary

Siltstone

Siltstone (primarily SiO2 with clay minerals)

Fossilized Solitary Rugose Coral (Horn Coral) (Order: Rugosa (e.g., Grewingkia or Heliophyllum); composed of Calcite (CaCO3) or Silica (SiO2)) — sedimentary

Fossilized Solitary Rugose Coral (Horn Coral)

Order: Rugosa (e.g., Grewingkia or Heliophyllum); composed of Calcite (CaCO3) or Silica (SiO2)

Limestone (Cliff Formation) (Limestone (predominantly CaCO3 as calcite)) — Sedimentary

Limestone (Cliff Formation)

Limestone (predominantly CaCO3 as calcite)

Coquina (Fossiliferous Limestone) (Coquina (Organic Clastic Limestone)) — sedimentary

Coquina (Fossiliferous Limestone)

Coquina (Organic Clastic Limestone)

Shale (Shale (clastic sedimentary rock)) — sedimentary

Shale

Shale (clastic sedimentary rock)

Chert (potentially Fossiliferous or Jasperoid) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (potentially Fossiliferous or Jasperoid)

Microcrystalline Quartz (SiO2)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Red Sandstone (Arenite (Ferruginous Sandstone)) — sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

Ferruginous Sandstone (Ironstone Nodules) (Ferruginous Sandstone with Limonite/Goethite coating (Fe2O3·H2O)) — sedimentary

Ferruginous Sandstone (Ironstone Nodules)

Ferruginous Sandstone with Limonite/Goethite coating (Fe2O3·H2O)

Sandstone (Ferruginous) (Arenite with Iron oxide staining (SiO2 with Fe2O3)) — sedimentary

Sandstone (Ferruginous)

Arenite with Iron oxide staining (SiO2 with Fe2O3)

Sandstone (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone

Arenite (composed primarily of SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)