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

Syringopora Fossil (Chain Coral) (Syringopora (Order Sarcinulata)) — fossil

Syringopora Fossil (Chain Coral)

Syringopora (Order Sarcinulata)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Glendonite (Calcite Pseudomorph after Ikaite) (Calcite (CaCO3) pseudomorph after Ikaite (CaCO3·6H2O)) — mineral

Glendonite (Calcite Pseudomorph after Ikaite)

Calcite (CaCO3) pseudomorph after Ikaite (CaCO3·6H2O)

Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

Sandstone (with Iron Staining) (Arenite (primarily SiO2 with Fe2O3/FeO(OH) oxides)) — sedimentary

Sandstone (with Iron Staining)

Arenite (primarily SiO2 with Fe2O3/FeO(OH) oxides)

Agate (Yellow Moss Agate) (Cryptocrystalline Quartz (SiO2)) — mineral

Agate (Yellow Moss Agate)

Cryptocrystalline Quartz (SiO2)

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

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pearl (Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)) — mineral

Pearl

Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)

Schist (Schist) — metamorphic

Schist

Schist

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

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

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions

Desert Rose (Gypsum Rose) (Calcium Sulfate Dihydrate (CaSO4·2H2O)) — mineral

Desert Rose (Gypsum Rose)

Calcium Sulfate Dihydrate (CaSO4·2H2O)

Tumbled brown jasper (Microcrystalline quartz/chalcedony (SiO₂), commonly iron-oxide stained) — sedimentary

Tumbled brown jasper

Microcrystalline quartz/chalcedony (SiO₂), commonly iron-oxide stained

Unakite (Unakite (Epidotized Granite)) — metamorphic

Unakite

Unakite (Epidotized Granite)

River Pebble (Quartzite or Chert) (Silicon Dioxide (SiO2)) — metamorphic or sedimentary

River Pebble (Quartzite or Chert)

Silicon Dioxide (SiO2)

metamorphic or sedimentary

Granite (Phaneritic Igneous Rock) — igneous

Granite

Phaneritic Igneous Rock

Pebble (Lithified rock fragment / Sedimentary clast) — sedimentary

Pebble

Lithified rock fragment / Sedimentary clast

Sandstone (Micaceous) (Clastic Sedimentary Rock (primarily SiO2 with Mica)) — sedimentary

Sandstone (Micaceous)

Clastic Sedimentary Rock (primarily SiO2 with Mica)

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

Petrified Wood

Silicified wood (primarily quartz, SiO2)

Amethyst (SiO2 (Silicon Dioxide with Iron impurities)) — mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

Greenschist (Greenschist (chlorite-epidote schist)) — metamorphic

Greenschist

Greenschist (chlorite-epidote schist)

Sandstone (Sandstone (Arenite)) — sedimentary

Sandstone

Sandstone (Arenite)

Jasper (Silicon dioxide (SiO2)) — mineral

Jasper

Silicon dioxide (SiO2)

Pink Granite (Phaneritic Quartz-Feldspar Plutonic Rock) — igneous

Pink Granite

Phaneritic Quartz-Feldspar Plutonic Rock

Sandstone (likely Greywacke or Lithic Sandstone) (Arenite / Wacke) — sedimentary

Sandstone (likely Greywacke or Lithic Sandstone)

Arenite / Wacke

Peach Moonstone (Potassium Aluminum Silicate (KAlSi3O8)) — mineral

Peach Moonstone

Potassium Aluminum Silicate (KAlSi3O8)

Crinoid Stem Fossil (Indian Bead) (Crinoid ossicle (Echinodermata)) — fossil

Crinoid Stem Fossil (Indian Bead)

Crinoid ossicle (Echinodermata)

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

Chert (variant Flint)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (primarily Quartz or Chalcedony, SiO2)) — mineral

Petrified Wood

Silicified Wood (primarily Quartz or Chalcedony, SiO2)

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

Chalcedony (Agate/Chert variety)

Silicon Dioxide (SiO2)

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

Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite

Granite (Phaneritic Felsic Igneous Rock) — igneous

Granite

Phaneritic Felsic Igneous Rock

Sandstone (Arenite (SiO2 based with mineral cement)) — sedimentary

Sandstone

Arenite (SiO2 based with mineral cement)

Quartz with Host Rock (SiO2 (Quartz) with fine-grained Matrix) — sedimentary

Quartz with Host Rock

SiO2 (Quartz) with fine-grained Matrix

Serpentinite (often called Jade or Nephrite substitute) (Serpentinite (composed primarily of Antigorite, Lizardite, or Chrysotile)) — metamorphic

Serpentinite (often called Jade or Nephrite substitute)

Serpentinite (composed primarily of Antigorite, Lizardite, or Chrysotile)

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

Petrified Wood

Silicified Wood (primarily SiO2)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

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

Brown Jasper / Chert Pebbles

Microcrystalline Quartz (SiO2) with iron oxide impurities

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

Chert (specifically Jasper/Flint pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert Pebble (Jasper variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble (Jasper variety)

Microcrystalline Quartz (SiO2)

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

Chert (Flint variety)

Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2