Rock Identifier

Category

Organic Structure (Not A Rock)

Browse organic structure (not a rock) specimens identified by the Rock Identifier community.

Learn about Organic Structure (Not A Rock) in the encyclopedia

Bituminous Shale

Bituminous Shale

Black Shale

Oil Shale

Petrified Wood

Crocodile Jasper

Crocodile Jasper

Opalized Wood

Rock Salt

Coral Rock

Rock Gypsum

Asphalt Rock

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

River/Stream Pebble (Clast / Detrital Grain / Rounded Sedimentary Particle (Compositionally variable, commonly Quartz, Feldspar, Chert, or other resistant rock fragments)) — Mineral, specifically a rock fragment

River/Stream Pebble

Clast / Detrital Grain / Rounded Sedimentary Particle (Compositionally variable, commonly Quartz, Feldspar, Chert, or other resistant rock fragments)

Mineral, specifically a rock fragment

Chert (Nodule/Pebble) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Nodule/Pebble)

Chert (Silicon Dioxide, SiO2)

Chert (specifically Pink/Tan Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Pink/Tan Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Pink Opal (Common Opal) (Amorphous Hydrated Silica (SiO2·nH2O)) — mineral

Pink Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O)

Dendritic Agate (Chalcedony (SiO2) with manganese/iron oxide inclusions) — mineral

Dendritic Agate

Chalcedony (SiO2) with manganese/iron oxide inclusions

Septarian Nodule (Dragon Stone) (Septarian concretion (composition: CaCO3 - Calcite, Aragonite, and Siderite/Limestone)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian concretion (composition: CaCO3 - Calcite, Aragonite, and Siderite/Limestone)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

Fossiliferous Limestone (Coquina / Shell Limestone) (CaCO3 (Calcium Carbonate)) — sedimentary

Fossiliferous Limestone (Coquina / Shell Limestone)

CaCO3 (Calcium Carbonate)

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

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Mookaite Jasper (Silicified Radiolarite (SiO2)) — sedimentary

Mookaite Jasper

Silicified Radiolarite (SiO2)

Amber (Succinite (organic hydrocarbon)) — mineraloid

Amber

Succinite (organic hydrocarbon)

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

Chert Nodule

Chert (Microcrystalline Silicon Dioxide, SiO2)

Tree Agate (or Moss Agate) (Dendritic Agate (Silicon Dioxide - SiO2)) — mineral

Tree Agate (or Moss Agate)

Dendritic Agate (Silicon Dioxide - SiO2)

Petrified Wood (Silicified wood (primarily quartz, SiO2)) — fossil

Petrified Wood

Silicified wood (primarily quartz, SiO2)

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

Chert (Yellow Jasper/Flint)

Microcrystalline Quartz (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Slate (Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)) — metamorphic

Slate

Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)

Druzy Quartz on Vesicular Basalt (Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock) — igneous

Druzy Quartz on Vesicular Basalt

Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock

Limestone ( weathered ) / Chert Nodular Rock (Sedimentary rock (primarily Calcium Carbonate, CaCO3, with Microcrystalline Quartz, SiO2)) — sedimentary

Limestone ( weathered ) / Chert Nodular Rock

Sedimentary rock (primarily Calcium Carbonate, CaCO3, with Microcrystalline Quartz, SiO2)

Dendritic Agate (Tree Agate) (Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions) — mineral

Dendritic Agate (Tree Agate)

Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions

Limestone with Chert or Siltstone bands (Sedimentary carbonate rock (CaCO3) often with siliceous impurities) — sedimentary

Limestone with Chert or Siltstone bands

Sedimentary carbonate rock (CaCO3) often with siliceous impurities

Chert Pebble with Quartz Veining (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble with Quartz Veining

Microcrystalline Quartz (SiO2)

Jasper with Quartz Vein (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Jasper with Quartz Vein

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Dragon Stone (Ohko Stone (Argillaceous sedimentary rock)) — sedimentary

Dragon Stone

Ohko Stone (Argillaceous sedimentary rock)

Fossiliferous Shale Matrix (Clastic Sedimentary Rock with Brachiopod or Mollusk shell fragments) — sedimentary

Fossiliferous Shale Matrix

Clastic Sedimentary Rock with Brachiopod or Mollusk shell fragments

Chert (specifically Banded Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Banded Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz (Druzy) in host rock (SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)) — Mineral

Quartz (Druzy) in host rock

SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)

Chert (Jasper / Petrified Wood) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper / Petrified Wood)

Microcrystalline Quartz (SiO2)

Fossiliferous Limestone (Coquina / Shell Limestone) (Bioclastic Limestone (CaCO3)) — sedimentary

Fossiliferous Limestone (Coquina / Shell Limestone)

Bioclastic Limestone (CaCO3)

Liesegang Ring Siltstone (Siltstone with iron oxide Liesegang bands) — sedimentary

Liesegang Ring Siltstone

Siltstone with iron oxide Liesegang bands

Moss Agate (Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides

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

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert (Microcrystalline silicon dioxide (SiO2)) — sedimentary

Banded Chert

Microcrystalline silicon dioxide (SiO2)

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

Petoskey Stone

Hexagonaria percarinata (Fossilized Coral)

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

Fossilized Gastropod (Snail)

Class Gastropoda (internal mold or 'steinkern')

Pink Opal (Amorphous Hydrous Silica (SiO2·nH2O)) — mineral

Pink Opal

Amorphous Hydrous Silica (SiO2·nH2O)

Fossil-bearing sedimentary rock, possibly fossil wood or bone (Indeterminate silicified/carbonate fossil in sandstone or mudstone) — fossil

Fossil-bearing sedimentary rock, possibly fossil wood or bone

Indeterminate silicified/carbonate fossil in sandstone or mudstone

Fossil Brachiopod (Phylum Brachiopoda) — fossil

Fossil Brachiopod

Phylum Brachiopoda

Coquina Limestone (Fossiliferous Limestone) (Calcareous bioclastic sedimentary rock (CaCO3)) — sedimentary

Coquina Limestone (Fossiliferous Limestone)

Calcareous bioclastic sedimentary rock (CaCO3)

Chert (often called Flint or Jasper) (Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)