Rock Identifier

Category

Rock

Browse rock specimens identified by the Rock Identifier community.

Limestone (Calcareous sedimentary rock (primarily Calcium Carbonate, CaCO3)) — sedimentary

Limestone

Calcareous sedimentary rock (primarily Calcium Carbonate, CaCO3)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Limestone (specifically Grainstone or Micrite) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (specifically Grainstone or Micrite)

Calcium Carbonate (CaCO3)

Sandstone (Arenite (Sedimentary rock comprising sand-sized grains)) — sedimentary

Sandstone

Arenite (Sedimentary rock comprising sand-sized grains)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Quartzite (Quartzite (composed mainly of SiO2)) — metamorphic

Quartzite

Quartzite (composed mainly of SiO2)

Granite Cobble (Granite (Phaneritic Quartz-Feldspar Felsic Rock)) — igneous

Granite Cobble

Granite (Phaneritic Quartz-Feldspar Felsic Rock)

Dendritic Agate or Spotted Quartzite (Silicon Dioxide (SiO2) with inclusions) — metamorphic

Dendritic Agate or Spotted Quartzite

Silicon Dioxide (SiO2) with inclusions

Quartz Vein in Host Rock (Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix) — Metamorphic or Igneous (context dependent)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix

Metamorphic or Igneous (context dependent)

Quartz-veined Sedimentary Rock (Hydrothermally veined Clastic Sedimentary Rock (SiO2 veins in Matrix)) — sedimentary

Quartz-veined Sedimentary Rock

Hydrothermally veined Clastic Sedimentary Rock (SiO2 veins in Matrix)

Unakite (Epidotized Granite) — metamorphic

Unakite

Epidotized Granite

Chert with Asphaltum (or Tar) (Silica (SiO2) with natural Bitumen/Asphaltum) — sedimentary

Chert with Asphaltum (or Tar)

Silica (SiO2) with natural Bitumen/Asphaltum

Granite (Phaneritic Plutonic Felsic Rock (K-Feldspar + Quartz + Plagioclase)) — igneous

Granite

Phaneritic Plutonic Felsic Rock (K-Feldspar + Quartz + Plagioclase)

Sandstone (with possibly iron oxides and other minerals) (Sandstone) — Sedimentary rock

Sandstone (with possibly iron oxides and other minerals)

Sandstone

Sedimentary rock

Blue Lace Agate (Agate (Variety of Chalcedony, SiO2)) — sedimentary

Blue Lace Agate

Agate (Variety of Chalcedony, SiO2)

River Quartzite (River Rock) (Quartzite (SiO2)) — metamorphic

River Quartzite (River Rock)

Quartzite (SiO2)

Ferruginous Sandstone (with Iron Oxide staining) (Clastic Sedimentary Rock - Quartz Arenite/Wacke) — sedimentary

Ferruginous Sandstone (with Iron Oxide staining)

Clastic Sedimentary Rock - Quartz Arenite/Wacke

Quartz Vein in Host Rock (Silicon Dioxide (SiO2)) — mineral

Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Common Opal with Host Rock (Opal (Hydrated silica, SiO2·nH2O)) — mineral

Common Opal with Host Rock

Opal (Hydrated silica, SiO2·nH2O)

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

Amethyst Geode

Silicon Dioxide with impurities (SiO2)

Quartz (Vein Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Smoky Quartz (Smoky Quartz (SiO2: Silicon Dioxide)) — mineral

Smoky Quartz

Smoky Quartz (SiO2: Silicon Dioxide)

Pink Tourmaline (Rubellite) (Elbaite (Tourmaline group) - Na(Li,Al)3Al6(BO3)3Si6O18(OH)4) — mineral

Pink Tourmaline (Rubellite)

Elbaite (Tourmaline group) - Na(Li,Al)3Al6(BO3)3Si6O18(OH)4

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

Agate (or Chalcedony)

Silicon Dioxide (SiO2)

Carnelian Agate (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Carnelian Agate

Silicon Dioxide (SiO2) with iron oxide impurities

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Sandstone (Banded) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Banded)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone (Quartzite-rich) (Clastic sedimentary rock (SiO2 primary)) — sedimentary

Sandstone (Quartzite-rich)

Clastic sedimentary rock (SiO2 primary)

Basalt (Water-worn Pavement Stone) (Basalt (Mafic Extrusive Igneous Rock)) — igneous

Basalt (Water-worn Pavement Stone)

Basalt (Mafic Extrusive Igneous Rock)

Pumice (Pumice (a highly vesicular volcanic rock)) — igneous

Pumice

Pumice (a highly vesicular volcanic rock)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Agate (specifically Carnelian Agate or Lake Superior style Agate) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Agate (specifically Carnelian Agate or Lake Superior style Agate)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Basalt with Vesicle/Vug (Basalt (Aphanitic Mafic Igneous Rock)) — igneous

Basalt with Vesicle/Vug

Basalt (Aphanitic Mafic Igneous Rock)

Blue Apatite (Apatite - Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite - Ca5(PO4)3(F,Cl,OH)

Garnet (Almandine (Fe3Al2(SiO4)3)) — mineral

Garnet

Almandine (Fe3Al2(SiO4)3)

Quartzite (River Cobble) (SiO2 (Quartz-rich Metamorphic Rock)) — metamorphic

Quartzite (River Cobble)

SiO2 (Quartz-rich Metamorphic Rock)

Basalt with Quartz Veining (Basalt (Mafic Volcanic Rock with SiO2)) — igneous

Basalt with Quartz Veining

Basalt (Mafic Volcanic Rock with SiO2)

Granite (Granite (Phaneritic intrusive igneous rock)) — igneous

Granite

Granite (Phaneritic intrusive igneous rock)

Limestone (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Tiger's Eye (Rough) (Pseudomorph of Quartz after Crocidolite (SiO2 with FeOOH inclusions)) — mineral

Tiger's Eye (Rough)

Pseudomorph of Quartz after Crocidolite (SiO2 with FeOOH inclusions)

Granite (Phaneritic Intrusive Igneous Rock (Granite)) — igneous

Granite

Phaneritic Intrusive Igneous Rock (Granite)