Rock Identifier

Category

Rock

Browse rock specimens identified by the Rock Identifier community.

Basalt with Granite Inclusions (Xenoliths) (Mafic igneous rock (Basalt) with Sialic minerals) — igneous

Basalt with Granite Inclusions (Xenoliths)

Mafic igneous rock (Basalt) with Sialic minerals

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

Sandstone

Clastic sedimentary rock (primarily SiO2)

Basalt (Basalt (Aphanitic-fine grained mafic igneous rock)) — igneous

Basalt

Basalt (Aphanitic-fine grained mafic igneous rock)

Quartz Vein in Host Rock (Quartz (SiO2) in Mafic or Sedimentary Matrix) — igneous

Quartz Vein in Host Rock

Quartz (SiO2) in Mafic or Sedimentary Matrix

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Sandstone (Sandstone (clastic sedimentary rock)) — Rock

Sandstone

Sandstone (clastic sedimentary rock)

Quartz Vein in Sandstone (Sandstone with Hydrothermal Quartz (SiO2)) — sedimentary

Quartz Vein in Sandstone

Sandstone with Hydrothermal Quartz (SiO2)

Basalt (Basalt) — igneous

Basalt

Basalt

Granodiorite with Quartz Veining (Granodiorite (containing Plagioclase Feldspar, Quartz, and Biotite/Hornblende) with Quartz (SiO2) veins) — igneous

Granodiorite with Quartz Veining

Granodiorite (containing Plagioclase Feldspar, Quartz, and Biotite/Hornblende) with Quartz (SiO2) veins

Banded Slate or Siltstone with Quartz/Calcite Veins (Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)) — metamorphic

Banded Slate or Siltstone with Quartz/Calcite Veins

Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)

Granodiorite (Phaneritic-textured Intrusive Granodiorite) — igneous

Granodiorite

Phaneritic-textured Intrusive Granodiorite

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Diorite (Diorite (Intermediate intrusive igneous rock)) — igneous

Diorite

Diorite (Intermediate intrusive igneous rock)

River Pebble (Gravel) (Clastic sedimentary rock (likely Siltstone or Mudstone pebble; SiO2 with various impurities)) — sedimentary

River Pebble (Gravel)

Clastic sedimentary rock (likely Siltstone or Mudstone pebble; SiO2 with various impurities)

Druzy Quartz on Matrix (likely Limestone or Sandstone) (Silicon Dioxide (SiO2) with various trace impurities) — Mineral on Sedimentary Rock

Druzy Quartz on Matrix (likely Limestone or Sandstone)

Silicon Dioxide (SiO2) with various trace impurities

Mineral on Sedimentary Rock

Botryoidal Chalcedony (Desert Rose / Agate) (Silicon Dioxide (SiO₂)) — Mineral variant

Botryoidal Chalcedony (Desert Rose / Agate)

Silicon Dioxide (SiO₂)

Mineral variant

Porphyritic Basalt (River Rock) (Porphyritic Basalt) — igneous

Porphyritic Basalt (River Rock)

Porphyritic Basalt

Sandstone with Quarzite clasts (Arenite (SiO2 based)) — sedimentary

Sandstone with Quarzite clasts

Arenite (SiO2 based)

Chert (Agatized/Chalcedony variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Agatized/Chalcedony variety)

Microcrystalline Quartz (SiO2)

Pebble or Cobble (likely composed of sandstone or conglomerate) (Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)) — Sedimentary Rock (possibly a conglomerate or coarse-grained sandstone)

Pebble or Cobble (likely composed of sandstone or conglomerate)

Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)

Sedimentary Rock (possibly a conglomerate or coarse-grained sandstone)

Basalt (Afanitic Mafic Basalt) — igneous

Basalt

Afanitic Mafic Basalt

Basalt (Mafic volcanic rock (primarily plagioclase, pyroxene, and olivine)) — Igneous

Basalt

Mafic volcanic rock (primarily plagioclase, pyroxene, and olivine)

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

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

Basalt with Iron Oxidation (Lattice/Veined) (Mafic Volcanic Rock (principally Plagioclase and Pyroxene)) — igneous

Basalt with Iron Oxidation (Lattice/Veined)

Mafic Volcanic Rock (principally Plagioclase and Pyroxene)

Basalt with Plagioclase Phenocrysts (Porphyritic Basalt) — igneous

Basalt with Plagioclase Phenocrysts

Porphyritic Basalt

Conglomerate (Conglomerate (Detrital Sedimentary Rock)) — sedimentary

Conglomerate

Conglomerate (Detrital Sedimentary Rock)

Vesicular Basalt (Scoria) (Vesicular Basalt) — igneous

Vesicular Basalt (Scoria)

Vesicular Basalt

Ferruginous Sandstone (Ironstone) (Arenite with Limonite/Goethite cement) — sedimentary

Ferruginous Sandstone (Ironstone)

Arenite with Limonite/Goethite cement

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)

Moonstone (Orthoclase (Potassium Aluminum Silicate), Formula: (K,Na)AlSi3O8) — mineral

Moonstone

Orthoclase (Potassium Aluminum Silicate), Formula: (K,Na)AlSi3O8

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Schist (Schist (metamorphic rock)) — metamorphic

Schist

Schist (metamorphic rock)

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

Chert (Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Agate Geode (Silicon Dioxide (SiO2)) — mineral

Agate Geode

Silicon Dioxide (SiO2)

Basalt with Calcite Veins (Basalt (containing CaCO3 inclusions)) — igneous

Basalt with Calcite Veins

Basalt (containing CaCO3 inclusions)

Porphyritic Basalt (Porphyritic Basalt (with Plagioclase phenocrysts)) — igneous

Porphyritic Basalt

Porphyritic Basalt (with Plagioclase phenocrysts)

Porphyritic Basalt (with Pyrolusite or Iron-oxide staining) (Porphyritic Basalt (Mafic Extrusive)) — igneous

Porphyritic Basalt (with Pyrolusite or Iron-oxide staining)

Porphyritic Basalt (Mafic Extrusive)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Bauxite (Laterite Clay) (Bauxite (mixture of Hydrous Aluminum Oxides: Gibbsite Al(OH)3, Boehmite and Diaspore AlO(OH))) — sedimentary

Bauxite (Laterite Clay)

Bauxite (mixture of Hydrous Aluminum Oxides: Gibbsite Al(OH)3, Boehmite and Diaspore AlO(OH))

Sandstone (lithic wacke) (Arenite / Lithic Wacke (mostly SiO2 with rock fragments)) — sedimentary

Sandstone (lithic wacke)

Arenite / Lithic Wacke (mostly SiO2 with rock fragments)

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

Peach Moonstone

Potassium Aluminum Silicate (KAlSi3O8)

Druzy Quartz on Host Rock (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz on Host Rock

Silicon Dioxide (SiO2)