Rock Identifier

Category

Organic (Often Found By Beachcombers)

Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.

Chert (Yellow or Tan Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow or Tan Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (and Limestone) (Chert (consisting of Microcrystalline Quartz, SiO2)) — sedimentary

Chert (and Limestone)

Chert (consisting of Microcrystalline Quartz, SiO2)

Chert (and/or Flint) (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert (and/or Flint)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Limestone (Concretionary or Tufa) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Concretionary or Tufa)

Calcium Carbonate (CaCO3)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

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

Chert (specifically Jasper or Flint variant)

Microcrystalline Quartz (SiO2)

Green Moss Agate (Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite) — sedimentary

Green Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite

Amber (Succinite (with empirical formula approximately C10H16O)) — Organic Mineraloid

Amber

Succinite (with empirical formula approximately C10H16O)

Organic Mineraloid

Green Sandstone (Glauconitic Sandstone) — sedimentary

Green Sandstone

Glauconitic Sandstone

Quartz Geode (Silicon Dioxide (SiO2)) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2)

Chert (Field Pebble) (Microcrystalline / Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Field Pebble)

Microcrystalline / Cryptocrystalline Quartz (SiO2)

Yellow Chert (Microcrystalline Quartz) (Chert / SiO2 (Silicon Dioxide)) — sedimentary

Yellow Chert (Microcrystalline Quartz)

Chert / SiO2 (Silicon Dioxide)

Chert / Pink Flint (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert / Pink Flint

Cryptocrystalline Quartz (SiO2)

Pink Chert (Brecciated Jasmine/Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Pink Chert (Brecciated Jasmine/Jasper)

Silicon Dioxide (SiO2)

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

Chert (Chert / Flint)

Silicon Dioxide (SiO2)

Limestone (Porous/Travertine variant) (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Porous/Travertine variant)

Sedimentary Calcium Carbonate (CaCO3)

Brachiopod Fossil in Limestone (Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)) — sedimentary

Brachiopod Fossil in Limestone

Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)

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

Petrified Wood

Silicified Wood (primarily SiO₂ - Silicon Dioxide)

Amber (Succinite) — Organic mineraloid

Amber

Succinite

Organic mineraloid

Chert (Yellow/Tan) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow/Tan)

Microcrystalline Quartz (SiO2)

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

Chert (often called Flint)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)

Red Jasper (Microcrystalline Quartz (SiO2) with Hematite impurities) — sedimentary

Red Jasper

Microcrystalline Quartz (SiO2) with Hematite impurities

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2 - Quartz/Chalcedony replacement)) — Mineral / Fossil

Petrified Wood

Silicified Wood (SiO2 - Quartz/Chalcedony replacement)

Mineral / Fossil

Chert (often called Flint or Jasper) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Water and Silt (Sedimentary Environment) (Suspended Sediment / H2O (dihydrogen monoxide)) — sedimentary

Water and Silt (Sedimentary Environment)

Suspended Sediment / H2O (dihydrogen monoxide)

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

Chert (Grey Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (often called Flint)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Chert (with Iron Staining) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (with Iron Staining)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Arid Sandy Loam (Arenosols / Regosols) — sedimentary

Arid Sandy Loam

Arenosols / Regosols

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz Geode in Chert/Limestone Matrix (Silicon Dioxide (SiO2) within Sedimentary Host Rock) — sedimentary

Quartz Geode in Chert/Limestone Matrix

Silicon Dioxide (SiO2) within Sedimentary Host Rock

Ferruginous Chert (Microcrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Ferruginous Chert

Microcrystalline Quartz (SiO2) with Iron Oxides

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

Limestone (Weathered)

Calcium Carbonate (CaCO3)

Chert (Nodular or Fossiliferous) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Nodular or Fossiliferous)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Chert (Quartz Variety)

Chert (Silicon Dioxide, SiO2)

Moss Agate (Silicon Dioxide (SiO2) with inclusions) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions

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

Chert (Red/Pink Jasper subtype)

Silicon Dioxide (SiO2)

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

Chert (Iron-stained)

Chert (primarily Microcrystalline Quartz, SiO2)