Rock Identifier

Category

Organic (Pseudo Geological)

Browse organic (pseudo geological) specimens identified by the Rock Identifier community.

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Chert / Flint (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert / Flint

Chert (Silicon Dioxide, SiO2)

Chert (Jasper/Quartzite Pebble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Quartzite Pebble)

Silicon Dioxide (SiO2)

Limestone (Crushed Gravel) (Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Limestone (Crushed Gravel)

Limestone (Calcium Carbonate, CaCO3)

Manganese-coated Sandstone (Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)) — sedimentary

Manganese-coated Sandstone

Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)

Honey Calcite (Calcium Carbonate (CaCO3)) — mineral

Honey Calcite

Calcium Carbonate (CaCO3)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossiliferous Limestone (Biomicrite / Limestone with fossils) — sedimentary

Fossiliferous Limestone

Biomicrite / Limestone with fossils

Sandstone Concretion (Arenaceous concretion (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone Concretion

Arenaceous concretion (primarily SiO2 with Fe2O3 staining)

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

Chert (specifically Flint or Jasper variant)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified wood (Quartz/Chalcedony replacement)) — fossil

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement)

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

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood / Chalcedony (SiO2)) — mineral

Petrified Wood

Silicified Wood / Chalcedony (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Geode (Unopened) (Silica-rich concretion (SiO2)) — sedimentary

Geode (Unopened)

Silica-rich concretion (SiO2)

Olive Sea Shell Fossil (Oliva sp. (Calcium Carbonate, CaCO3)) — fossil

Olive Sea Shell Fossil

Oliva sp. (Calcium Carbonate, CaCO3)

Ironstone Concretion (Goethite-rich Siltstone / Siderite (FeCO3)) — sedimentary

Ironstone Concretion

Goethite-rich Siltstone / Siderite (FeCO3)

Fossilized Shark Tooth (Chondrichthyes (Class) fossil) — fossil

Fossilized Shark Tooth

Chondrichthyes (Class) fossil

Pearl (Pearl; primarily aragonite (CaCO₃) with conchiolin) — gemstone

Pearl

Pearl; primarily aragonite (CaCO₃) with conchiolin

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert (Flint) with Limestone Matrix (Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)) — sedimentary

Chert (Flint) with Limestone Matrix

Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)

Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Amber (Succinite / Fossilized Resin (C10H16O)) — fossil

Amber

Succinite / Fossilized Resin (C10H16O)

Calcite crystal cluster (Calcite (calcium carbonate, CaCO₃)) — mineral

Calcite crystal cluster

Calcite (calcium carbonate, CaCO₃)

Tumbled banded agate (likely chalcedony) (Microcrystalline quartz, SiO₂; probable banded chalcedony/agate) — mineral

Tumbled banded agate (likely chalcedony)

Microcrystalline quartz, SiO₂; probable banded chalcedony/agate

Petrified Wood (Silicified wood (Quartz/Chalcedony/Opal)) — sedimentary

Petrified Wood

Silicified wood (Quartz/Chalcedony/Opal)

Honey calcite (yellow calcite) (Calcite, calcium carbonate (CaCO₃)) — mineral

Honey calcite (yellow calcite)

Calcite, calcium carbonate (CaCO₃)

Graphite-rich metamorphic rock (likely graphite schist) (Graphite schist; predominantly graphitic carbon (C) with mica and quartz) — metamorphic

Graphite-rich metamorphic rock (likely graphite schist)

Graphite schist; predominantly graphitic carbon (C) with mica and quartz

Fossil-bearing ironstone or weathered concretion (Indeterminate; likely ferruginous sandstone/concretion containing a partial fossil impression) — fossil

Fossil-bearing ironstone or weathered concretion

Indeterminate; likely ferruginous sandstone/concretion containing a partial fossil impression

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variant)

Silicon Dioxide (SiO2)

Chert (specifically Gray/Blue Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Gray/Blue Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Graphite Schist (C (Carbonaceous Schist)) — metamorphic

Graphite Schist

C (Carbonaceous Schist)

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

Chert (Black Chert/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Green Calcite (Calcium Carbonate (CaCO3)) — mineral

Green Calcite

Calcium Carbonate (CaCO3)

Fossil Shell (Bivalve) (Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3) — sedimentary

Fossil Shell (Bivalve)

Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3

Likely pyrite-bearing rock fragment (Pyrite, FeS₂, possibly in a dark host rock) — mineral

Likely pyrite-bearing rock fragment

Pyrite, FeS₂, possibly in a dark host rock

Fossilized tooth, likely shark tooth (Fossilized selachian tooth; possibly a worn Otodus or related shark tooth) — fossil

Fossilized tooth, likely shark tooth

Fossilized selachian tooth; possibly a worn Otodus or related shark tooth