Rock Identifier

Category

Organic Specimen (Fossil)

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

Granite Pebble (Felsic intrusive igneous rock (consisting primarily of Quartz and Feldspar)) — igneous

Granite Pebble

Felsic intrusive igneous rock (consisting primarily of Quartz and Feldspar)

Chert (Common Opal/Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Common Opal/Chalcedony)

Microcrystalline Quartz (SiO2)

Chert (Jasper) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper)

Cryptocrystalline Quartz (SiO2)

Quartzite (River Cobble) (Quartzite (predominantly SiO2)) — metamorphic

Quartzite (River Cobble)

Quartzite (predominantly SiO2)

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

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

Tree Agate (or Moss Agate), faceted into a crystal tower (Dendritic Agate (Silicon Dioxide, SiO2)) — Mineral

Tree Agate (or Moss Agate), faceted into a crystal tower

Dendritic Agate (Silicon Dioxide, SiO2)

Dendritic Agate (Tumbled) (Silicon Dioxide (SiO2) with inclusions) — mineral

Dendritic Agate (Tumbled)

Silicon Dioxide (SiO2) with inclusions

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

Chert (and Limestone)

Silicon Dioxide (SiO2)

Fulonite (Fulgurite-like) (Fulgurite (SiO2 fused silica/lechatelierite)) — Metamorphic (Pseudo-igneous)

Fulonite (Fulgurite-like)

Fulgurite (SiO2 fused silica/lechatelierite)

Metamorphic (Pseudo-igneous)

Jasper with Manganese Dendrites (Silicon Dioxide (SiO2) with Oxide Mineral Inclusions) — sedimentary

Jasper with Manganese Dendrites

Silicon Dioxide (SiO2) with Oxide Mineral Inclusions

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

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Coquina / Fossiliferous Limestone (Fossiliferous Calcarenite (Calcium carbonate, CaCO3)) — sedimentary

Coquina / Fossiliferous Limestone

Fossiliferous Calcarenite (Calcium carbonate, CaCO3)

Basalt with Amygdules (Amygdaloidal Basalt) — igneous

Basalt with Amygdules

Amygdaloidal Basalt

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

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

Chert (Iron-stained)

Microcrystalline quartz (SiO2)

Chert (Yellow Jasper variant) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Yellow Jasper variant)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Granite (Granite (Felsic Plutonic Rock / SiO2 + Al2O3 + K2O + Na2O + CaO + FeO + MgO)) — igneous

Granite

Granite (Felsic Plutonic Rock / SiO2 + Al2O3 + K2O + Na2O + CaO + FeO + MgO)

Yellow Quartzite (River Pebble) (Quartzite (primarily SiO2)) — metamorphic

Yellow Quartzite (River Pebble)

Quartzite (primarily SiO2)

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

Chert (Flint/Jasper variety)

Microcrystalline Quartz (SiO2)

Stromatolite (Cyanobacteria fossilized formation (CaCO3)) — sedimentary

Stromatolite

Cyanobacteria fossilized formation (CaCO3)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Quartzite Pebble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Pebble

Quartzite (primarily SiO2)

Granite (Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica)) — igneous

Granite

Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica)

Mookaite Jasper (Radiolarite (Silica, SiO2)) — sedimentary

Mookaite Jasper

Radiolarite (Silica, SiO2)

Mookaite Jasper (Silicified Radiolarite (SiO2 with impurities)) — sedimentary

Mookaite Jasper

Silicified Radiolarite (SiO2 with impurities)

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Sandstone (Cross-bedded Drill Core) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Cross-bedded Drill Core)

Clastic Sedimentary Rock (primarily SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Milky Quartz (Gold-bearing Prospecting Specimen) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (Gold-bearing Prospecting Specimen)

Silicon Dioxide (SiO2)

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

Chert (and/or Flint)

Silicon Dioxide (SiO2)

Mookaite Jasper (Silicified Radiolarite (SiO2)) — sedimentary

Mookaite Jasper

Silicified Radiolarite (SiO2)

Chert (River Pebble) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Picture Jasper (Silicon Dioxide (SiO2) with mineral inclusions) — sedimentary

Picture Jasper

Silicon Dioxide (SiO2) with mineral inclusions

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Chert (specifically Flint or Dark Chalcedony) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Dark Chalcedony)

Silicon Dioxide (SiO2)

Chert (Jasper variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper variety)

Microcrystalline quartz (SiO2)

Diorite (River Cobble) (Phaneritic Intermediate Plutonic Rock) — igneous

Diorite (River Cobble)

Phaneritic Intermediate Plutonic Rock

Fossilized Rugose Coral (Rugosa (Order Rugosa, typically fossilized in Limestone)) — sedimentary

Fossilized Rugose Coral

Rugosa (Order Rugosa, typically fossilized in Limestone)

Sandstone (likely Arkose or Quartz Sandstone) (Arenite (SiO2 + varied clasts)) — sedimentary

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 + varied clasts)

Limestone Breccia (Sedimentary Breccia (Calcareous)) — sedimentary

Limestone Breccia

Sedimentary Breccia (Calcareous)

Sandstone Concretion (Clastic Sedimentary Rock (primarily SiO2 with mineral cement)) — sedimentary

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)