Rock Identifier

Category

Rock

Browse rock specimens identified by the Rock Identifier community.

Learn about Rock in the encyclopedia

Rock Gypsum

Coral Rock

Rock Salt

Asphalt Rock

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

Cataclasite

Anorthosite

Peridotite

Gondite

Phosphorite

Epidosite

Weathered basalt or volcanic breccia (Fine-grained mafic volcanic rock, likely basalt (plagioclase–pyroxene ± olivine), possibly brecciated) — igneous

Weathered basalt or volcanic breccia

Fine-grained mafic volcanic rock, likely basalt (plagioclase–pyroxene ± olivine), possibly brecciated

Copper Ore / Altered Granodiorite (Cupriferous rock with silicate gangue) — mineral

Copper Ore / Altered Granodiorite

Cupriferous rock with silicate gangue

Vesicular Basalt (Lava Rock) (Vesicular Basalt) — igneous

Vesicular Basalt (Lava Rock)

Vesicular Basalt

Granite Pebble (Intrusive Igneous Rock) — igneous

Granite Pebble

Intrusive Igneous Rock

Granite (Granite) — igneous

Granite

Granite

Shale (Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)) — sedimentary

Shale

Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)

Vesicular Basalt (or Scoria) (Mafic extrusive igneous rock with vesicles) — igneous

Vesicular Basalt (or Scoria)

Mafic extrusive igneous rock with vesicles

Generic Pebble (Lithic Fragment) — sedimentary

Generic Pebble

Lithic Fragment

Serpentinite (Serpentinite (composed primarily of Serpentine group minerals (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)) — metamorphic

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Granite (Granite) — igneous

Granite

Granite

Granite Pebble (Granite (Plutonic Igneous Rock)) — igneous

Granite Pebble

Granite (Plutonic Igneous Rock)

Quartzite Pebble (Stream-rounded Quartz/Quartzite Gravel) (Quartzite / Silicon Dioxide (SiO2)) — metamorphic

Quartzite Pebble (Stream-rounded Quartz/Quartzite Gravel)

Quartzite / Silicon Dioxide (SiO2)

Unidentified rock fragments (Indeterminate; likely a weathered, iron-stained silicate rock) — mineral

Unidentified rock fragments

Indeterminate; likely a weathered, iron-stained silicate rock

Weathered gneissic or granitic rock (Quartz–feldspar–biotite gneiss (tentative; possibly weathered granite)) — metamorphic

Weathered gneissic or granitic rock

Quartz–feldspar–biotite gneiss (tentative; possibly weathered granite)

Quartz Vein in Amphibolite / Gneiss (Quartz (SiO2) in Mafic Metamorphic Host Rock) — metamorphic

Quartz Vein in Amphibolite / Gneiss

Quartz (SiO2) in Mafic Metamorphic Host Rock

Rounded quartz-veined pebble (Likely quartz-veined metamorphic rock; exact host rock is indeterminate from the image) — metamorphic

Rounded quartz-veined pebble

Likely quartz-veined metamorphic rock; exact host rock is indeterminate from the image

Vesicular Basalt (or Scoraceous Basalt) (Basalt (Vesicular texture)) — igneous

Vesicular Basalt (or Scoraceous Basalt)

Basalt (Vesicular texture)

Serpentine (Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4) — metamorphic

Serpentine

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

K-Feldspar Granite Fragment (Felsic Plutonic Rock (Granite)) — igneous

K-Feldspar Granite Fragment

Felsic Plutonic Rock (Granite)

Garnet Schist (Garnetiferous Micaceous Schist) — metamorphic

Garnet Schist

Garnetiferous Micaceous Schist

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Unidentified dark pebble (Unknown) — rock

Unidentified dark pebble

Unknown

River Pebble (Granite/Gneiss) (Granitic Pebble / Quartz-Feldspar Aggregate) — igneous

River Pebble (Granite/Gneiss)

Granitic Pebble / Quartz-Feldspar Aggregate

River Pebble (Siltstone / Fine-grained Sandstone) (Sedimentary Pebble (Siliclastic)) — sedimentary

River Pebble (Siltstone / Fine-grained Sandstone)

Sedimentary Pebble (Siliclastic)

Quartzite Pebble (Iron-stained Quartz) (Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions) — metamorphic

Quartzite Pebble (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Smoky Quartz and Chalcedony Geode Fragment (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz and Chalcedony Geode Fragment

Silicon Dioxide (SiO2)

Veined Limestone (Micrite) with Quartz/Calcite Veins (Calcium Carbonate (CaCO3) with Silicate or Carbonate inclusions) — sedimentary

Veined Limestone (Micrite) with Quartz/Calcite Veins

Calcium Carbonate (CaCO3) with Silicate or Carbonate inclusions

Porphyritic Basalt (Porphyritic Basalt with Plagioclase Phenocrysts) — igneous

Porphyritic Basalt

Porphyritic Basalt with Plagioclase Phenocrysts

Geode (Quartz nodule / Chalcedony-lined cavity) — sedimentary

Geode

Quartz nodule / Chalcedony-lined cavity

Sandstone (Arenite (SiO2, often with CaCO3 or Fe2O3 cement)) — sedimentary

Sandstone

Arenite (SiO2, often with CaCO3 or Fe2O3 cement)

Serpentine (Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4) — metamorphic

Serpentine

Serpentinite (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

Serpentine (Antigorite, Lizardite, or Chrysotile (Mg3Si2O5(OH)4)) — metamorphic

Serpentine

Antigorite, Lizardite, or Chrysotile (Mg3Si2O5(OH)4)

Sandstone (Quartz Sandstone (predominantly)) — Sedimentary

Sandstone

Quartz Sandstone (predominantly)

Basalt with Xenolith (Extrusive Igneous Rock containing Mantle Xenolith) — igneous

Basalt with Xenolith

Extrusive Igneous Rock containing Mantle Xenolith

Chert (Jasper/Flint Pebble) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Flint Pebble)

Microcrystalline quartz (SiO2)

Granitic rock, likely weathered granite (Granite; primarily quartz, feldspar, and mica) — igneous

Granitic rock, likely weathered granite

Granite; primarily quartz, feldspar, and mica

Sandstone (Arenite (SiO2 dominant)) — sedimentary

Sandstone

Arenite (SiO2 dominant)

Shale or Slaty Mudstone (Argillaceous sedimentary rock) — sedimentary

Shale or Slaty Mudstone

Argillaceous sedimentary rock

Greenstone, likely altered basalt (Metabasalt (chlorite–actinolite–epidote assemblage), likely greenschist-facies greenstone) — metamorphic

Greenstone, likely altered basalt

Metabasalt (chlorite–actinolite–epidote assemblage), likely greenschist-facies greenstone

Granite (Phaneritic plutonic rock (primarily Quartz, Feldspar, and Mica)) — igneous

Granite

Phaneritic plutonic rock (primarily Quartz, Feldspar, and Mica)

Quartzite Pebble with Feldspar Vein (Quartzite (SiO2) with Feldspar (KAlSi3O8)) — metamorphic

Quartzite Pebble with Feldspar Vein

Quartzite (SiO2) with Feldspar (KAlSi3O8)

Schist (likely Mica Schist) (Mica Schist) — metamorphic

Schist (likely Mica Schist)

Mica Schist