Rock Identifier

Category

Organic Specimen (Fossil)

Browse organic specimen (fossil) specimens identified by the Rock Identifier community.

Sandstone or Limestone (Arenite or Calcareous Sedimentary Rock) — Sedimentary

Sandstone or Limestone

Arenite or Calcareous Sedimentary Rock

Sandstone (Clastic Sedimentary Rock (composed primarily of Quartz: SiO2)) — sedimentary

Sandstone

Clastic Sedimentary Rock (composed primarily of Quartz: SiO2)

Red Sandstone (Arenite (primarily Quartz with Iron Oxide)) — sedimentary

Red Sandstone

Arenite (primarily Quartz with Iron Oxide)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Coquina (Biogenic Limestone (Calcite, CaCO3)) — sedimentary

Coquina

Biogenic Limestone (Calcite, CaCO3)

Chert (Nodular Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Nodular Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Conglomerate (Conglomerative Sedimentary Rock) — sedimentary

Conglomerate

Conglomerative Sedimentary Rock

Red Sandstone (Clastic sedimentary rock (primarily SiO2 with Fe2O3)) — sedimentary

Red Sandstone

Clastic sedimentary rock (primarily SiO2 with Fe2O3)

Flower Agate (Chalcedony with Opaque Spherulitic Inclusions (SiO2)) — Mineral

Flower Agate

Chalcedony with Opaque Spherulitic Inclusions (SiO2)

Sandstone (Arenite (primarily SiO2 - Silicon Dioxide)) — sedimentary

Sandstone

Arenite (primarily SiO2 - Silicon Dioxide)

Siltstone (Siltstone (primarily SiO2 with Al2O3 and Fe2O3)) — sedimentary

Siltstone

Siltstone (primarily SiO2 with Al2O3 and Fe2O3)

Marble (Recrystallized Calcite (CaCO3)) — metamorphic

Marble

Recrystallized Calcite (CaCO3)

Sandstone (Quartzose Sandstone) (Arenite (SiO2 principal component)) — sedimentary

Sandstone (Quartzose Sandstone)

Arenite (SiO2 principal component)

Sandstone (Weathered Pebble) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Weathered Pebble)

Arenite (primarily SiO2)

Chert (Jasper) (Silicon dioxide (SiO2)) — sedimentary

Chert (Jasper)

Silicon dioxide (SiO2)

Anthracite Coal (Anthracite (Carbon-based solid)) — metamorphic

Anthracite Coal

Anthracite (Carbon-based solid)

Siltstone (Siltstone (primarily composed of SiO2)) — sedimentary

Siltstone

Siltstone (primarily composed of SiO2)

Granitic Gneiss (Gneiss (Metamorphic Rock)) — metamorphic

Granitic Gneiss

Gneiss (Metamorphic Rock)

Fossilized Coral (Petoskey Stone type) (Hexagonaria percarinata (Fossilized Rugose Coral)) — sedimentary

Fossilized Coral (Petoskey Stone type)

Hexagonaria percarinata (Fossilized Rugose Coral)

Coquina (Biogenic Limestone (Calcite/Aragonite)) — sedimentary

Coquina

Biogenic Limestone (Calcite/Aragonite)

Sandstone (with manganese staining) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (with manganese staining)

Clastic sedimentary rock (primarily SiO2)

Petoskey Stone (Hexagonaria percarinata) — sedimentary

Petoskey Stone

Hexagonaria percarinata

Chert (variously known as Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (variously known as Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Ironstone (Limonitic Sandstone) (Ferruginous Sandstone (rich in Limonite: FeO(OH)·nH2O)) — sedimentary

Ironstone (Limonitic Sandstone)

Ferruginous Sandstone (rich in Limonite: FeO(OH)·nH2O)

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

Chert (and Flint)

Silicon Dioxide (SiO2)

Bivalve Fossil (Clam) (Class Bivalvia (Calcium Carbonate, CaCO3)) — sedimentary

Bivalve Fossil (Clam)

Class Bivalvia (Calcium Carbonate, CaCO3)

Chalk / Sedimentary Limestone (Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock) — sedimentary

Chalk / Sedimentary Limestone

Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock

Laterite (Laterite (Ferricrete)) — sedimentary

Laterite

Laterite (Ferricrete)

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

Chert (White Chert/Flint)

Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)

Chalk (Calcitic) (Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock) — sedimentary

Chalk (Calcitic)

Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock

Limestone (Calcite-rich Sedimentary Rock (CaCO3)) — sedimentary

Limestone

Calcite-rich Sedimentary Rock (CaCO3)

Chert / Flint (Microcrystalline Silica (SiO2)) — sedimentary

Chert / Flint

Microcrystalline Silica (SiO2)

Cockle Shell (Fossil or Recent) (Class Bivalvia, Family Cardiidae (e.g., Cerastoderma edule for common cockle)) — Sedimentary (Biogenic, a type of fossil)

Cockle Shell (Fossil or Recent)

Class Bivalvia, Family Cardiidae (e.g., Cerastoderma edule for common cockle)

Sedimentary (Biogenic, a type of fossil)

Chert (often called Flint) (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (often called Flint)

Chert (Cryptocrystalline Silica, SiO2)

Coral Fossil (Favosites) (Favosites (Calcite/Calcium Carbonate, CaCO3)) — sedimentary

Coral Fossil (Favosites)

Favosites (Calcite/Calcium Carbonate, CaCO3)

Horse Chestnut (Buckeye seed) (Aesculus hippocastanum seed) — Organic (Non-geological)

Horse Chestnut (Buckeye seed)

Aesculus hippocastanum seed

Organic (Non-geological)

Honeycomb Coral Fossil (Favosites (extinct genus of tabulate coral)) — sedimentary

Honeycomb Coral Fossil

Favosites (extinct genus of tabulate coral)

Amber (Succinite) — mineral

Amber

Succinite

Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image) (SiO₂ (silicon dioxide)) — Sedimentary

Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image)

SiO₂ (silicon dioxide)

Brachiopod Fossil in Chert (Phylum Brachiopoda within Microcrystalline Quartz (SiO2)) — sedimentary

Brachiopod Fossil in Chert

Phylum Brachiopoda within Microcrystalline Quartz (SiO2)

Petoskey Stone (Hexagonaria percarinata) — sedimentary

Petoskey Stone

Hexagonaria percarinata