Rock Identifier

Category

Organic Material

Browse organic material specimens identified by the Rock Identifier community.

Learn about Organic Material in the encyclopedia

Peat

Sapropel

Bituminous Shale

Bituminous Shale

Black Shale

Petrified Wood

Amber

Jet

Oil Shale

Pearl

Lizard Skin Jasper

Dunite

Opalized Wood

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Concrete or asphalt-like aggregate surface with a dark fragment (Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock) — sedimentary

Concrete or asphalt-like aggregate surface with a dark fragment

Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock

Quartz vein in host rock (Quartz (SiO₂), likely in a weathered carbonate or sedimentary matrix) — mineral

Quartz vein in host rock

Quartz (SiO₂), likely in a weathered carbonate or sedimentary matrix

Moss Agate / Chalcedony (Silicon Dioxide (SiO2)) — mineral

Moss Agate / Chalcedony

Silicon Dioxide (SiO2)

Zebra Marble (Metamorphosed Limestone (Recrystallized Calcite)) — metamorphic

Zebra Marble

Metamorphosed Limestone (Recrystallized Calcite)

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

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement of organic matter)

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

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Flint Pebble) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint Pebble)

Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Basanite / Jasperoid)

Microcrystalline Quartz (SiO2)

Polished operculum (“Shiva eye” shell) (Calcium-carbonate shell operculum, commonly from a turban snail (family Turbinidae); not a mineral specimen) — fossil

Polished operculum (“Shiva eye” shell)

Calcium-carbonate shell operculum, commonly from a turban snail (family Turbinidae); not a mineral specimen

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

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Agatized Fossil (Druzy Agate) (Silicon Dioxide (SiO2) replacing organic matter) — sedimentary

Agatized Fossil (Druzy Agate)

Silicon Dioxide (SiO2) replacing organic matter

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

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert (Silicon Dioxide (SiO2)) — sedimentary

Banded Chert

Silicon Dioxide (SiO2)

Crushed Limestone (Sedimentary Calcite/Dolomite Rock (CaCO3)) — sedimentary

Crushed Limestone

Sedimentary Calcite/Dolomite Rock (CaCO3)

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

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Calligraphy Stone (Mariam Jasper (Fossiliferous Limestone with Hematite and Iron)) — sedimentary

Calligraphy Stone

Mariam Jasper (Fossiliferous Limestone with Hematite and Iron)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Coquina or Fossiliferous Limestone (Fossiliferous Calcarenite (CaCO3)) — sedimentary

Coquina or Fossiliferous Limestone

Fossiliferous Calcarenite (CaCO3)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Chert (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert

Cryptocrystalline Quartz (SiO2)

Petrified Wood Fragment (Silicified Wood (SiO2)) — fossil

Petrified Wood Fragment

Silicified Wood (SiO2)

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

Limestone (Fossiliferous)

Calcium Carbonate (CaCO3)

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

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Flint) (Chert (SiO2)) — sedimentary

Chert (Flint)

Chert (SiO2)

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

Chert (Chalcedony/Flint)

Silicon Dioxide (SiO2)

Flint (Chert (Silicon dioxide, SiO2)) — sedimentary

Flint

Chert (Silicon dioxide, SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Carved red coral bead (likely coral or coral-colored resin) (Corallium spp. (precious coral; calcium carbonate, CaCO₃)) — gemstone

Carved red coral bead (likely coral or coral-colored resin)

Corallium spp. (precious coral; calcium carbonate, CaCO₃)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Chert (Flint Nodules) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint Nodules)

Silicon Dioxide (SiO2)

Polished amber-like chalcedony/jasper (Microcrystalline quartz (SiO₂), likely iron-stained chalcedony or jasper; amber cannot be confirmed visually) — mineral

Polished amber-like chalcedony/jasper

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony or jasper; amber cannot be confirmed visually

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

Chert (variations include Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Chert (Flint)

Silicon Dioxide (SiO2)

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

Petrified Wood

Silicified Wood (SiO2 permineralization)

Coprolite (Fossilized Feces) — fossil

Coprolite

Fossilized Feces

Fossilized wood (petrified wood) (Silicified fossil wood; commonly quartz (SiO₂) replacing wood tissues) — fossil

Fossilized wood (petrified wood)

Silicified fossil wood; commonly quartz (SiO₂) replacing wood tissues

Chert (often called Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint)

Silicon Dioxide (SiO2)