Rock Identifier

Category

Organic Specimen (Fossil)

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

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Sandstone (with Iron Staining) (Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 oxides)) — sedimentary

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 oxides)

Porous Quartzite (Metamorphosed Quartz-rich Sandstone (SiO2)) — metamorphic

Porous Quartzite

Metamorphosed Quartz-rich Sandstone (SiO2)

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

Crushed Limestone

Calcite-rich Sedimentary Rock (CaCO3)

Amber (Succinicum (Succinite); C10H16O) — Mineraloid (Organic)

Amber

Succinicum (Succinite); C10H16O

Mineraloid (Organic)

Sandstone (Ferruginous) (Arenite (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Amber (Succinicum (Organic polymer, largely C10H16O)) — Organic Mineral

Amber

Succinicum (Organic polymer, largely C10H16O)

Organic Mineral

Shale (sub-type: Carbonaceous Shale) (Lutaceous Sedimentary Rock) — sedimentary

Shale (sub-type: Carbonaceous Shale)

Lutaceous Sedimentary Rock

Sandstone (Arenite (primarily SiO2 with iron oxide cementation)) — sedimentary

Sandstone

Arenite (primarily SiO2 with iron oxide cementation)

Fossilized Sea Urchin (Echinoid) (Echinoidea (Fossil specimen, often replaced by Calcite or Silica)) — sedimentary

Fossilized Sea Urchin (Echinoid)

Echinoidea (Fossil specimen, often replaced by Calcite or Silica)

Sandstone (with banding/weathering) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (with banding/weathering)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone (likely Graywacke or Arkose variant) (Clastic Sedimentary Rock (Lithic Sandstone)) — sedimentary

Sandstone (likely Graywacke or Arkose variant)

Clastic Sedimentary Rock (Lithic Sandstone)

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

Coal (most likely Bituminous or Anthracite)

Coal (organic sedimentary rock)

Petrified Wood (Silicified wood (Quartz/Chalcedony - SiO2)) — sedimentary

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Glauconitic Sandstone (Greensand pebble) (Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone (Greensand pebble)

Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Sandstone (with potential mineral staining/concretions) (Arenite (SiO2 based)) — sedimentary

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Sandstone (Quartz-rich Pebble) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartz-rich Pebble)

Arenite (primarily SiO2)

Petrified Wood (Silicified Wood (SiO2 - Silicon Dioxide)) — mineral

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Chert (containing a small fossil) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (containing a small fossil)

Microcrystalline Quartz (SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Coquina / Fossiliferous Limestone (Calcite-rich Bioclastic Sedimentary Rock (CaCO3)) — sedimentary

Coquina / Fossiliferous Limestone

Calcite-rich Bioclastic Sedimentary Rock (CaCO3)

Petrified Wood (Silicified wood (primarily Silicon Dioxide - SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily Silicon Dioxide - SiO2)

Amber-bearing Coal/Sedimentary Rock (Bituminous coal or carbonaceous siltstone with Fossilized Tree Resin (C10H16O)) — sedimentary

Amber-bearing Coal/Sedimentary Rock

Bituminous coal or carbonaceous siltstone with Fossilized Tree Resin (C10H16O)

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

Chert Pebble

Microcrystalline or cryptocrystalline Quartz (SiO2)

Echinoidea (Fossil Sea Urchin) (Echinodermata Echinoidea) — sedimentary

Echinoidea (Fossil Sea Urchin)

Echinodermata Echinoidea

Chert (Smooth River Pebble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Smooth River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Limestone (specifically fossiliferous/skeletal limestone) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (specifically fossiliferous/skeletal limestone)

Calcium Carbonate (CaCO3)

Sandstone (likely Quartzose Sandstone with mineral staining) (Arenite (composed mainly of SiO2)) — sedimentary

Sandstone (likely Quartzose Sandstone with mineral staining)

Arenite (composed mainly of SiO2)

Fossilized Brachiopod/Bivalve in Limestone (Brachiopoda or Bivalvia fossil in Calcite/Limestone (CaCO3)) — sedimentary

Fossilized Brachiopod/Bivalve in Limestone

Brachiopoda or Bivalvia fossil in Calcite/Limestone (CaCO3)

Ironstone Concretion (Iron-rich Mudstone) (Siderite / Geothite concretion (FeCO3 / FeO(OH))) — sedimentary

Ironstone Concretion (Iron-rich Mudstone)

Siderite / Geothite concretion (FeCO3 / FeO(OH))

Chert (variations include Flint) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (variations include Flint)

Chert (Silicon Dioxide, SiO2)

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

Sandstone

Arenite (composed primarily of SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Chert (Jasper variety) with Iron Oxide staining (Cryptocrystalline Quartz (SiO2) with Goethite/Limonite impurities) — sedimentary

Chert (Jasper variety) with Iron Oxide staining

Cryptocrystalline Quartz (SiO2) with Goethite/Limonite impurities

Petrified Wood (Silicified Wood (SiO2 permineralization)) — sedimentary

Petrified Wood

Silicified Wood (SiO2 permineralization)

Fossiliferous Limestone (Bivalve Fossil) (Calcium Carbonate (CaCO3) with Bivalvia fossil) — sedimentary

Fossiliferous Limestone (Bivalve Fossil)

Calcium Carbonate (CaCO3) with Bivalvia fossil

Chert (often called Flint in this variation) (Silicon dioxide (SiO2) - Microcrystalline quartz) — sedimentary

Chert (often called Flint in this variation)

Silicon dioxide (SiO2) - Microcrystalline quartz

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

Chert (River Pebble)

Microcrystalline quartz (SiO2)

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

Chert (White Chert)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Limestone with Quartz/Calcite Veins (Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)) — sedimentary

Limestone with Quartz/Calcite Veins

Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)