Rock Identifier

Category

Organic Specimen (Fossil)

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

Learn about Organic Specimen (Fossil) in the encyclopedia

Petrified Wood

Amber

Jet

Opalized Wood

Chert with Limestone matrix (Microcrystalline silica (SiO2) in Calcite (CaCO3) matrix) — sedimentary

Chert with Limestone matrix

Microcrystalline silica (SiO2) in Calcite (CaCO3) matrix

Unidentified weathered rock fragments (Likely mixed silicate rocks; specific identification requires testing) — mineral

Unidentified weathered rock fragments

Likely mixed silicate rocks; specific identification requires testing

Green Jasper (Microcrystalline Quartz (Chalcedony), SiO2) — sedimentary

Green Jasper

Microcrystalline Quartz (Chalcedony), SiO2

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

Chert (Jasper/Agate)

Silicon Dioxide (SiO2)

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

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Chert (River Pebble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (River Pebble)

Silicon Dioxide (SiO2)

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

Chert (Smooth River Pebble)

Microcrystalline Quartz (SiO2)

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

Chert (Iron-stained)

Chert (SiO2)

Chert (River Stone) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (River Stone)

Microcrystalline Quartz (SiO2)

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

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Chert Pebble (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble

Microcrystalline Quartz (SiO2)

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

Chert (Quartz Variety)

Chert (Silicon Dioxide, SiO2)

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

Chert (often called Flint or River Stone)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Arrowhead Fragment) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead Fragment)

Microcrystalline Quartz (SiO2)

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

Chert (Jasper variety)

Chert (Silicon Dioxide, SiO2)

Chert (Yellow Jasper/Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper/Flint)

Microcrystalline Quartz (SiO2)

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Chert (Jasper/Agate variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Chert (Jasper) (Microcrystalline Quartz (SiO2) with iron oxide impurities) — sedimentary

Chert (Jasper)

Microcrystalline Quartz (SiO2) with iron oxide impurities

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

Chert (River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pyrite in Shale (Iron Disulfide (FeS2) in Sedimentary Shale) — mineral

Pyrite in Shale

Iron Disulfide (FeS2) in Sedimentary Shale

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

Chert (River Pebble)

Microcrystalline silica (SiO2)

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

Chert (Jasper/Quartzite Pebble)

Silicon Dioxide (SiO2)

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

Chert / Flint Pebble

Silicon Dioxide (SiO2)

Dendritic Moss Agate (Chalcedony (Silicon Dioxide, SiO2) with inclusions) — mineral

Dendritic Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions

Chert / Flint (Chert (SiO2)) — sedimentary

Chert / Flint

Chert (SiO2)

Chert Nodules in Limestone (Cryptocrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)) — sedimentary

Chert Nodules in Limestone

Cryptocrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)

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

Banded Chert

Chert (Silicon Dioxide, SiO2)

Crinoid Stem Fossils (Indian Beads / St. Cuthbert's Beads) (Crinoid columnal ossicles (phylum Echinodermata)) — fossil

Crinoid Stem Fossils (Indian Beads / St. Cuthbert's Beads)

Crinoid columnal ossicles (phylum Echinodermata)

Septarian Nodule or Mud Crack Fossil (Septarian Nodule (Concretion)) — sedimentary

Septarian Nodule or Mud Crack Fossil

Septarian Nodule (Concretion)

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

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Chert (Green variety) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Green variety)

Chert (Silicon Dioxide, SiO2)

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Chalcedony (Agatized Coral / Rough Chalcedony Node) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Agatized Coral / Rough Chalcedony Node)

Silicon Dioxide (SiO2)

Chert (Iron-stained) (Silicon Dioxide (SiO2) with Iron Oxides) — sedimentary

Chert (Iron-stained)

Silicon Dioxide (SiO2) with Iron Oxides

Limestone (or Calcite Pebble) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (or Calcite Pebble)

Calcium Carbonate (CaCO3)

Mother of Pearl (Nacre) (Aragonite (layered with organic polymers), CaCO3) — mineral

Mother of Pearl (Nacre)

Aragonite (layered with organic polymers), CaCO3

Chert (specifically Flint or Gray Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Gray Chert)

Silicon Dioxide (SiO2)

Quartz (Chert/Chalcedony variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Chert (Iron-stained) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Iron-stained)

Silicon Dioxide (SiO2)

Brachiopod Fossil in Shale (Phylum Brachiopoda (often species of Order Spiriferida or Rhynchonellida)) — sedimentary

Brachiopod Fossil in Shale

Phylum Brachiopoda (often species of Order Spiriferida or Rhynchonellida)

Yellow Jasper (Silicon Dioxide (Microcrystalline Quartz, SiO2)) — sedimentary

Yellow Jasper

Silicon Dioxide (Microcrystalline Quartz, SiO2)