Rock Identifier

Category

Organic Specimen (Fossil)

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

Limestone (Limestone (Calcium Carbonate - CaCO3)) — sedimentary

Limestone

Limestone (Calcium Carbonate - CaCO3)

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

Petoskey Stone

Hexagonaria percarinata (Fossilized Coral)

Coquina Jasper (Fossiliferous Chalcedony (SiO2)) — sedimentary

Coquina Jasper

Fossiliferous Chalcedony (SiO2)

Fossiliferous Limestone with Rugose Coral (Rugosa (order), typically preserved in CaCO3 (Calcite)) — sedimentary

Fossiliferous Limestone with Rugose Coral

Rugosa (order), typically preserved in CaCO3 (Calcite)

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

Chert (Jasper)

Silicon Dioxide (SiO2)

Chert (specifically Flint or Common Opal variant) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Common Opal variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Script Jasper (Silicon Dioxide (SiO2) with impurities) — sedimentary

Script Jasper

Silicon Dioxide (SiO2) with impurities

Dendritic Opal (Opalized Chalcedony with Manganese Inclusions (SiO2 · nH2O)) — mineral

Dendritic Opal

Opalized Chalcedony with Manganese Inclusions (SiO2 · nH2O)

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

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Mookaite Jasper (Silicon Dioxide (SiO2) with various inclusions) — sedimentary

Mookaite Jasper

Silicon Dioxide (SiO2) with various inclusions

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Quartzite (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite

Metamorphosed Quartz Sandstone (SiO2)

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

Chert (often called Flint)

Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)

Chert (specifically Flint or Jasper variant) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (specifically Flint or Jasper variant)

Microcrystalline quartz (SiO2)

Pink Quartzite (Quartzite (SiO2)) — metamorphic

Pink Quartzite

Quartzite (SiO2)

Dendritic Jasper (River Stone) (Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions) — sedimentary

Dendritic Jasper (River Stone)

Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions

Ironstone Concretion (Pot Stone) (Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)) — sedimentary

Ironstone Concretion (Pot Stone)

Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)

Sandstone Concretion (Sandstone (Sedimentary Rock) with silica or calcite cement) — sedimentary

Sandstone Concretion

Sandstone (Sedimentary Rock) with silica or calcite cement

Tree Agate (Silicon Dioxide (SiO2) - Dendritic Agate/Chalcedony) — sedimentary

Tree Agate

Silicon Dioxide (SiO2) - Dendritic Agate/Chalcedony

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

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Sea Shell (Fighting Conch Fragment) (Calcium Carbonate (CaCO3) - Strombus alatus fragment) — sedimentary (biogenic)

Sea Shell (Fighting Conch Fragment)

Calcium Carbonate (CaCO3) - Strombus alatus fragment

sedimentary (biogenic)

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

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Montana Moss Agate (Chalcedony (Silicon Dioxide, SiO2)) — mineral

Montana Moss Agate

Chalcedony (Silicon Dioxide, SiO2)

Mookaite Jasper (Silicified Radiolarite (SiO2)) — sedimentary

Mookaite Jasper

Silicified Radiolarite (SiO2)

Mookaite Jasper (Radiolarite (Silica with iron oxides like Goethite and Hematite)) — sedimentary

Mookaite Jasper

Radiolarite (Silica with iron oxides like Goethite and Hematite)

Dendritic Agate (Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions) — mineral

Dendritic Agate

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Amber (Succinite) — Mineraloid

Amber

Succinite

Chert (specifically Flint or Dark Chert) (Chert (SiO2)) — sedimentary

Chert (specifically Flint or Dark Chert)

Chert (SiO2)

Kambaba Jasper (Stromatolite / Fossilized Algae (Rhyolitic structure)) — sedimentary

Kambaba Jasper

Stromatolite / Fossilized Algae (Rhyolitic structure)

Sandstone (Banded) (Clastic Sedimentary Rock (primarily Quartz, SiO2)) — sedimentary

Sandstone (Banded)

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Biggs Jasper (Picture Jasper) (Silicon Dioxide (SiO2) - Opaque Silicified Volcanic Ash) — sedimentary

Biggs Jasper (Picture Jasper)

Silicon Dioxide (SiO2) - Opaque Silicified Volcanic Ash

Tiger's Eye (Titanium-containing Quartz (Silica: SiO2)) — Mineral

Tiger's Eye

Titanium-containing Quartz (Silica: SiO2)

Fulgurite (Fulgurite (Lechatelierite), amorphous SiO2) — metamorphic

Fulgurite

Fulgurite (Lechatelierite), amorphous SiO2

Diorite (weathered) (Intermediate plutonic igneous rock) — igneous

Diorite (weathered)

Intermediate plutonic igneous rock

Quartzite Cobble (Quartzite (SiO2)) — metamorphic

Quartzite Cobble

Quartzite (SiO2)

Ironstone Concretion (Coprolite-like) (Goethite/Hematite Siderite Spheroid (FeCO3 or FeO(OH))) — sedimentary

Ironstone Concretion (Coprolite-like)

Goethite/Hematite Siderite Spheroid (FeCO3 or FeO(OH))

Dragon Vein Agate (Chalcedony (cryptocrystalline silica, SiO2) variety Agate) — mineral

Dragon Vein Agate

Chalcedony (cryptocrystalline silica, SiO2) variety Agate

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

Chert / Microcrystalline Quartz

Chert (SiO2)

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

Chert (or Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Common Opal variant) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Common Opal variant)

Silicon Dioxide (SiO2)

Chert (and/or Siltstone River Pebble) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (and/or Siltstone River Pebble)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (specifically Flint or Jasper variant) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)