Rock Identifier

Category

Organic (Anthropogenic)

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

Learn about Organic (Anthropogenic) in the encyclopedia

Sapropel

Bituminous Shale

Bituminous Shale

Black Shale

Petrified Wood

Amber

Jet

Peat

Oil Shale

Pearl

Lizard Skin Jasper

Opalized Wood

Coral Rock

Chert (variously known as Flint or Jasper) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (variously known as Flint or Jasper)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (Red/Pink Jasper subtype) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Red/Pink Jasper subtype)

Silicon Dioxide (SiO2)

Chert (Hag Stone / Hole Stone) (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert (Hag Stone / Hole Stone)

Chert (Cryptocrystalline variety of Quartz, SiO2)

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

Possible fossilized ammonite or concretion (Indeterminate fossil specimen; possibly an ammonoid mold/cast in iron-rich sedimentary rock) — fossil

Possible fossilized ammonite or concretion

Indeterminate fossil specimen; possibly an ammonoid mold/cast in iron-rich sedimentary rock

Septarian Nodule (Septarian Concretion (Calcite, Aragonite, and Limestone)) — sedimentary

Septarian Nodule

Septarian Concretion (Calcite, Aragonite, and Limestone)

Petrified Palm Wood (Palmoxylon) — fossil

Petrified Palm Wood

Palmoxylon

Petrified Wood (Silicified wood (permineralized wood)) — fossil

Petrified Wood

Silicified wood (permineralized wood)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2 / Quartz pseudomorph after wood)) — fossil

Petrified Wood

Silicified Wood (SiO2 / Quartz pseudomorph after wood)

Chert (specifically Flint or Dark Chert) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (specifically Flint or Dark Chert)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (primarily SiO2 - Silicon Dioxide)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Chert (specifically Red Chert or Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Red Chert or Jasper)

Microcrystalline Quartz (SiO2)

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

Banded Chert (or Flint)

Microcrystalline Quartz (SiO2)

Chert (Brown variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Brown variety)

Silicon Dioxide (SiO2)

Red Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Red Jasper

Jasper (Silicon Dioxide, SiO2)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Chert (Chert Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossiliferous Limestone (Crinoidal) (Calcium Carbonate (CaCO3) - Limestone containing bioclasts) — sedimentary

Fossiliferous Limestone (Crinoidal)

Calcium Carbonate (CaCO3) - Limestone containing bioclasts

Fossilized Shark Tooth (Partial) (Elasmobranchii (fossil tooth fragment)) — sedimentary

Fossilized Shark Tooth (Partial)

Elasmobranchii (fossil tooth fragment)

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

Chert (often called Flint or Jasper)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

Chert Pebble with Quartz Veining (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble with Quartz Veining

Microcrystalline Quartz (SiO2)

Banded Chert (River Siltstone) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert (River Siltstone)

Microcrystalline Quartz (SiO2)

Glauconitic Sandstone (Greensand) (Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone (Greensand)

Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)

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

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Chert (specifically Pink/Tan Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Pink/Tan Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper variation)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Quartz Variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Quartz Variety)

Silicon Dioxide (SiO2)

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

Chert (Jasper/Flint variant)

Silicon Dioxide (SiO2)

Chert (Arrowhead/Artifact Fragment) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead/Artifact Fragment)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (specifically Gray/Blue Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Yellow Jasper (Silicon Dioxide (SiO2) with iron inclusions) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron inclusions

Graphite Schist (C (Carbonaceous Schist)) — metamorphic

Graphite Schist

C (Carbonaceous Schist)

Fossil Coral (Favosites) (Favosites (Order: Tabulata, Phylum: Cnidaria)) — sedimentary

Fossil Coral (Favosites)

Favosites (Order: Tabulata, Phylum: Cnidaria)

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

Chert (Black Chert/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossiliferous Limestone (containing Brachiopods) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (containing Brachiopods)

Biogenic Limestone (Calcium Carbonate, CaCO3)