Rock Identifier

Category

Rock

Browse rock specimens identified by the Rock Identifier community.

Learn about Rock in the encyclopedia

Rock Gypsum

Coral Rock

Asphalt Rock

Rock Salt

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

Anorthosite

Cataclasite

Peridotite

Phosphorite

Gondite

Dunite

Quartz with Schist Inclusion (Crystalline Silicon Dioxide (SiO2) with Muscovite/Biotite Schist) — metamorphic

Quartz with Schist Inclusion

Crystalline Silicon Dioxide (SiO2) with Muscovite/Biotite Schist

Agate (Common Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Agate (Common Chalcedony)

Silicon Dioxide (SiO2)

Druzy Quartz on Chalcedony Matrix (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz on Chalcedony Matrix

Silicon Dioxide (SiO2)

Sandstone (Quartzose) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartzose)

Arenite (primarily SiO2)

Garnet Schist (Almandine Garnet-bearing Mica Schist) — metamorphic

Garnet Schist

Almandine Garnet-bearing Mica Schist

Sandstone (Ferruginous) (Arenite (Siliclastic Sedimentary Rock)) — sedimentary

Sandstone (Ferruginous)

Arenite (Siliclastic Sedimentary Rock)

Quartz (Druzy on Matrix) (Silicon Dioxide (SiO2)) — mineral

Quartz (Druzy on Matrix)

Silicon Dioxide (SiO2)

Vesicular Basalt (Scoria) (Basalt (Vesicular texture)) — igneous

Vesicular Basalt (Scoria)

Basalt (Vesicular texture)

Agate Geode (Silicon Dioxide (SiO2) - Chalcedony / Quartz Variety) — Mineral

Agate Geode

Silicon Dioxide (SiO2) - Chalcedony / Quartz Variety

Note: Item is not a geological specimen (n/a) — none

Note: Item is not a geological specimen

n/a

Agate (Silicon dioxide (Chalcedony), SiO2) — gemstone

Agate

Silicon dioxide (Chalcedony), SiO2

Agate (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Agate

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Granite (Phaneritic Plutonic Igneous Rock (primarily composed of quartz, alkali feldspar, and plagioclase)) — igneous

Granite

Phaneritic Plutonic Igneous Rock (primarily composed of quartz, alkali feldspar, and plagioclase)

Quartz (Milky/Crystalline) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Crystalline)

Silicon Dioxide (SiO2)

Basalt (Basalt) — igneous

Basalt

Basalt

Serpentine (Antigorite, Lizardite, or Chrysotile (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4) — metamorphic

Serpentine

Antigorite, Lizardite, or Chrysotile (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

Quartz Vein in Siltstone (Siltstone with Quartz (SiO2) inclusion) — sedimentary

Quartz Vein in Siltstone

Siltstone with Quartz (SiO2) inclusion

Quartz Geode with Chalcedony (Silicon Dioxide (SiO2) in Geode Form) — sedimentary

Quartz Geode with Chalcedony

Silicon Dioxide (SiO2) in Geode Form

Quartz Geode (Silicon Dioxide (SiO2) within a geode) — mineral

Quartz Geode

Silicon Dioxide (SiO2) within a geode

Metaconglomerate (Protolith: Conglomerate (comprising SiO2, Al2O3, etc.)) — metamorphic

Metaconglomerate

Protolith: Conglomerate (comprising SiO2, Al2O3, etc.)

Basalt with Calcite Veins (Basalt (Mafic Volcanic Rock)) — igneous

Basalt with Calcite Veins

Basalt (Mafic Volcanic Rock)

Banded Gneiss (Gneiss (High-grade regional metamorphic rock)) — metamorphic

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Basalt (Basalt (Mafic volcanic rock)) — igneous

Basalt

Basalt (Mafic volcanic rock)

River cobble (Greywacke/Sandstone) (Sandstone / Greywacke) — sedimentary

River cobble (Greywacke/Sandstone)

Sandstone / Greywacke

Quartz Pebble with Host Rock / Schist Matrix (Silicon Dioxide (SiO2) with Metamorphic Host Rock) — sedimentary

Quartz Pebble with Host Rock / Schist Matrix

Silicon Dioxide (SiO2) with Metamorphic Host Rock

Pebble (Clast (specifically a granule or small pebble)) — Sedimentary

Pebble

Clast (specifically a granule or small pebble)

Quartz Veined Rock (Likely Graywacke or Quartzite) (Silicon Dioxide (SiO2) veins in Metasedimentary matrix) — metamorphic

Quartz Veined Rock (Likely Graywacke or Quartzite)

Silicon Dioxide (SiO2) veins in Metasedimentary matrix

Limonite (after Pyrite Pseudomorph) (Limonite (Hydrated Iron Oxide Mixture, FeO(OH)·nH2O)) — mineral

Limonite (after Pyrite Pseudomorph)

Limonite (Hydrated Iron Oxide Mixture, FeO(OH)·nH2O)

Agate Geode with Quartz Druzy (Chalcedony (SiO2) and Quartz (SiO2)) — mineral

Agate Geode with Quartz Druzy

Chalcedony (SiO2) and Quartz (SiO2)

Quartz Druzy (Silicon Dioxide (SiO2)) — mineral

Quartz Druzy

Silicon Dioxide (SiO2)

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

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

Banded Sandstone (Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)) — sedimentary

Banded Sandstone

Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)

Chert (Arrowhead) (Chert (primarily Microcrystalline Silica, SiO2)) — sedimentary

Chert (Arrowhead)

Chert (primarily Microcrystalline Silica, SiO2)

Gravel and Sand Aggregate (Unconsolidated Clastic Sediment) — sedimentary

Gravel and Sand Aggregate

Unconsolidated Clastic Sediment

Unidentifiable Rock Fragment — Uncertain

Unidentifiable Rock Fragment

Conglomerate (Conglomerate rock) — sedimentary

Conglomerate

Conglomerate rock

Sandstone or Limestone (Sedimentary Rock) — Sedimentary

Sandstone or Limestone

Sedimentary Rock

River Rock (Basalt or Sandstone) (Clastic Sedimentary Rock or Extrusive Mafic Igneous Rock) — igneous or sedimentary

River Rock (Basalt or Sandstone)

Clastic Sedimentary Rock or Extrusive Mafic Igneous Rock

igneous or sedimentary

Glacial Cobble (likely Granitic or Gneissic) (Granite/Gneiss Glacial Erratic) — igneous

Glacial Cobble (likely Granitic or Gneissic)

Granite/Gneiss Glacial Erratic

Granite (Granite) — Igneous

Granite

Granite

Pink Granite (Plagioclase-Quartz-K-Feldspar Granite) — igneous

Pink Granite

Plagioclase-Quartz-K-Feldspar Granite

Quartz Geode (Quartz (Silicon Dioxide - SiO2) within a Chalcedony and Limonite shell) — sedimentary

Quartz Geode

Quartz (Silicon Dioxide - SiO2) within a Chalcedony and Limonite shell