Rock Identifier

Category

Organic (Often Found By Beachcombers)

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

Amber (Cherry or Red variety) (Succinite (with various trace amounts of organic compounds)) — Organic Gemstone (not a rock)

Amber (Cherry or Red variety)

Succinite (with various trace amounts of organic compounds)

Organic Gemstone (not a rock)

Chert (often called Flint in archaeological contexts) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint in archaeological contexts)

Silicon Dioxide (SiO2)

Chert (Grey-Green Var.) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Grey-Green Var.)

Silicon Dioxide (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Pink Opal / Peruvian Opal (Hydrated amorphous silicon dioxide (SiO2·nH2O)) — Mineral

Pink Opal / Peruvian Opal

Hydrated amorphous silicon dioxide (SiO2·nH2O)

Banded Chert (Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)) — Sedimentary

Banded Chert

Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)) — Mineral/Fossil (Sedimentary context)

Petrified Wood

Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)

Mineral/Fossil (Sedimentary context)

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

Chert (specifically Chert Nodule/Flint)

Chert (Silicon Dioxide, SiO2)

Chert / River Pebble (Microcrystalline Silica (SiO2)) — sedimentary

Chert / River Pebble

Microcrystalline Silica (SiO2)

Chert (specifically Iron-stained River Cobble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Iron-stained River Cobble)

Silicon Dioxide (SiO2)

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

Petrified Wood

Silicified wood (primarily SiO2)

Pyrite (Iron Pyrite (FeS2)) — mineral

Pyrite

Iron Pyrite (FeS2)

Dog (Sleeping) (Canis familiaris (or Canis lupus familiaris)) — Organic/Biological

Dog (Sleeping)

Canis familiaris (or Canis lupus familiaris)

Organic/Biological

Amber (Amber (C10H16O)) — mineral

Amber

Amber (C10H16O)

Grass (Organic Matter/Soil) (Poaceae (family of monocotyledonous flowering plants)) — Organic Materia (Not a rock or mineral)

Grass (Organic Matter/Soil)

Poaceae (family of monocotyledonous flowering plants)

Organic Materia (Not a rock or mineral)

Amber (Succinite (Fossilized Resin C10H16O)) — Organic Mineraloid

Amber

Succinite (Fossilized Resin C10H16O)

Organic Mineraloid

Black Marble with Quartz Veining (Metamorphosed Limestone (Recrystallized CaCO3)) — metamorphic

Black Marble with Quartz Veining

Metamorphosed Limestone (Recrystallized CaCO3)

Amber (Succinite (fossilized resin)) — mineral

Amber

Succinite (fossilized resin)

Fossiliferous Limestone with Rugose Coral (Lithostrotionella (Limestone Matrix - CaCO3)) — sedimentary

Fossiliferous Limestone with Rugose Coral

Lithostrotionella (Limestone Matrix - CaCO3)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides

Amber (Succinite) — Organic (Mineraloid)

Amber

Succinite

Organic (Mineraloid)

Fossilized Gastropod (Snail) (Class Gastropoda (internal mold or 'steinkern')) — sedimentary

Fossilized Gastropod (Snail)

Class Gastropoda (internal mold or 'steinkern')

Amber (Fossilized Resin (C10H16O)) — mineral

Amber

Fossilized Resin (C10H16O)

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

Moss Agate

Silicon Dioxide with inclusions (SiO2 + impurities)

Amber (Cherry Amber) (Succinite (C10H16O)) — Organic Gemstone

Amber (Cherry Amber)

Succinite (C10H16O)

Organic Gemstone

Zebra Marble (Metamorphosed Alabaster/Limestone (CaCO3)) — metamorphic

Zebra Marble

Metamorphosed Alabaster/Limestone (CaCO3)

Amber (Succinite (Formula: C10H16O)) — Organic Mineraloid

Amber

Succinite (Formula: C10H16O)

Organic Mineraloid

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Amber (Succinite (C10H16O)) — mineraloid

Amber

Succinite (C10H16O)

Chert / Quartz Pebble (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert / Quartz Pebble

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (often called Flint or Jasper when red) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (often called Flint or Jasper when red)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Petrified Wood

Silicified wood (primarily Silicon Dioxide - SiO2)

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

Chert (often called Flint or River Stone)

Microcrystalline Quartz (SiO2)

Paper (Cellulose) (Cellulose (C6H10O5)n) — Organic (Anthropogenic)

Paper (Cellulose)

Cellulose (C6H10O5)n

Organic (Anthropogenic)

Anthracite Coal (Anthracite (Carbon-based organic sedimentary/metamorphic rock)) — metamorphic

Anthracite Coal

Anthracite (Carbon-based organic sedimentary/metamorphic rock)

Amber (Copal) (Organic gemstone, fossilized tree resin (often immature amber or copal)) — Mineral

Amber (Copal)

Organic gemstone, fossilized tree resin (often immature amber or copal)

Pearl (Calcium carbonate (CaCO3) in the form of Aragonite or Calcite) — mineral

Pearl

Calcium carbonate (CaCO3) in the form of Aragonite or Calcite

Amber (Fossilized tree resin (not a true mineral as it is organic and amorphous); Chemical formula is highly variable, but often approximated as C10H16O.) — Mineral

Amber

Fossilized tree resin (not a true mineral as it is organic and amorphous); Chemical formula is highly variable, but often approximated as C10H16O.

Chert (varietal known as Jasper or Flint) (Silicon Dioxide (SiO2)) — Sedimentary Rock

Chert (varietal known as Jasper or Flint)

Silicon Dioxide (SiO2)

Sedimentary Rock

Amber (Succinite (organic hydrocarbon)) — mineraloid

Amber

Succinite (organic hydrocarbon)