Rock Identifier

Category

Organic (Biological Organism)

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

Chert (Hagstone/Gasket Rock variant) (Chert (SiO2)) — sedimentary

Chert (Hagstone/Gasket Rock variant)

Chert (SiO2)

Crinoid Stem Fossil (Class Crinoidea (Phylum Echinodermata), primarily Calcium Carbonate (CaCO3)) — sedimentary

Crinoid Stem Fossil

Class Crinoidea (Phylum Echinodermata), primarily Calcium Carbonate (CaCO3)

Pink Opal (Hydrated Silica (SiO2·nH2O) with Palygorskite inclusions) — Mineraloid

Pink Opal

Hydrated Silica (SiO2·nH2O) with Palygorskite inclusions

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

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)

Chert (Nodule) (Cryptocrystalline Silica (SiO2)) — sedimentary

Chert (Nodule)

Cryptocrystalline Silica (SiO2)

Septarian Nodule (Dragon Stone) (Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)

Chert (specifically a stream-worn Chert Nodule) (Sedimentary Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically a stream-worn Chert Nodule)

Sedimentary Cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO₂ - Silicon Dioxide)

Ironstone Concretion / Limonite Node (Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)) — sedimentary

Ironstone Concretion / Limonite Node

Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)

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

Black Marble with Quartz Veining

Metamorphosed Limestone (Recrystallized CaCO3)

Chert Pebble / Brachiopod Fossil Internal Mold (Silicon Dioxide (SiO2) / Fossil: Brachiopoda (generic internal mold)) — sedimentary

Chert Pebble / Brachiopod Fossil Internal Mold

Silicon Dioxide (SiO2) / Fossil: Brachiopoda (generic internal mold)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petoskey Stone (Hexagonaria percarinata (Fossilized Coral)) — sedimentary

Petoskey Stone

Hexagonaria percarinata (Fossilized Coral)

Chert (Limestone-based) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Limestone-based)

Silicon Dioxide (SiO2)

Graphite (Graphite (Carbon, C)) — Mineral

Graphite

Graphite (Carbon, C)

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

Pink Opal / Peruvian Opal

Hydrated amorphous silicon dioxide (SiO2·nH2O)

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

Fossilized Gastropod (Snail)

Class Gastropoda (internal mold or 'steinkern')

Chert (Chert (microcrystalline quartz, SiO2)) — Sedimentary

Chert

Chert (microcrystalline quartz, SiO2)

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

Petrified Wood

Silicified wood (primarily SiO2)

Chert (Arrowhead or Projectile Point) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead or Projectile Point)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Calcite (likely a tumbled specimen) (Calcite (CaCO
3
)) — Mineral

Calcite (likely a tumbled specimen)

Calcite (CaCO 3 )

Hand-Drawn Trading Card (Amateur Artwork) (Cellulose-based substrate with wax/graphite/ink deposit (n/a for minerals)) — Organic/Synthetic Composite (Paper and Pigment)

Hand-Drawn Trading Card (Amateur Artwork)

Cellulose-based substrate with wax/graphite/ink deposit (n/a for minerals)

Organic/Synthetic Composite (Paper and Pigment)

Septarian Nodule (Septarian Dragon Stone) (Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)) — sedimentary

Septarian Nodule (Septarian Dragon Stone)

Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)

Crushed Limestone (Calcium Carbonate (CaCO3)) — Sedimentary

Crushed Limestone

Calcium Carbonate (CaCO3)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Red Jasper (beads) (SiO₂ (Silicon Dioxide)) — Mineral, variety of chalcedony (microcrystalline quartz)

Red Jasper (beads)

SiO₂ (Silicon Dioxide)

Mineral, variety of chalcedony (microcrystalline quartz)

Chert (Chert (microcrystalline quartz)) — Sedimentary

Chert

Chert (microcrystalline quartz)

Chert (or Flint) (Chert (microcrystalline or cryptocrystalline quartz, SiO2)) — Sedimentary

Chert (or Flint)

Chert (microcrystalline or cryptocrystalline quartz, SiO2)

Chert (Jasper-like) (SiO2 (Cryptocrystalline Quartz)) — Sedimentary

Chert (Jasper-like)

SiO2 (Cryptocrystalline Quartz)

Red Jasper (Red Jasper (variety of Chalcedony, SiO₂)) — Mineral

Red Jasper

Red Jasper (variety of Chalcedony, SiO₂)

Chert (Flint) (SiO2 (predominantly microcrystalline or cryptocrystalline quartz)) — Sedimentary rock

Chert (Flint)

SiO2 (predominantly microcrystalline or cryptocrystalline quartz)

Sedimentary rock

Chert / Flint (a variety of Chert) (Chert (SiO2)) — Sedimentary Rock (technically a microcrystalline quartz mineral aggregate)

Chert / Flint (a variety of Chert)

Chert (SiO2)

Sedimentary Rock (technically a microcrystalline quartz mineral aggregate)

Chert (or Flint) (Chert (a cryptocrystalline variety of quartz, SiO2)) — sedimentary

Chert (or Flint)

Chert (a cryptocrystalline variety of quartz, SiO2)

Calcite (Calcite (Mineral; CaCO₃)) — Mineral

Calcite

Calcite (Mineral; CaCO₃)

Pyrite (Pyrite (Iron Disulfide), FeS2) — Mineral

Pyrite

Pyrite (Iron Disulfide), FeS2

Brown Jasper (Likely) (Jasper (Cryptocrystalline Silicon Dioxide - SiO2)) — Mineral

Brown Jasper (Likely)

Jasper (Cryptocrystalline Silicon Dioxide - SiO2)

Chert (varieties include Flint or Jasper) (Chert (cryptocrystalline quartz; SiO₂)) — Sedimentary

Chert (varieties include Flint or Jasper)

Chert (cryptocrystalline quartz; SiO₂)

Chert (Flint) (Chert (microcrystalline quartz)) — sedimentary

Chert (Flint)

Chert (microcrystalline quartz)

Calcite (Calcite (Calcium Carbonate, CaCO3)) — mineral

Calcite

Calcite (Calcium Carbonate, CaCO3)

Chert (or Flint) (SiO2 (predominantly microcrystalline quartz)) — Sedimentary

Chert (or Flint)

SiO2 (predominantly microcrystalline quartz)

Cherry Creek Jasper (also known as Red Creek Jasper or Cherry Creek Agate) (Jasper, microcrystalline quartz (SiO₂)) — Sedimentary Rock

Cherry Creek Jasper (also known as Red Creek Jasper or Cherry Creek Agate)

Jasper, microcrystalline quartz (SiO₂)

Sedimentary Rock

Mookaite Jasper (Siliceous (chert) sedimentary rock, a form of Jasper) — Sedimentary

Mookaite Jasper

Siliceous (chert) sedimentary rock, a form of Jasper