Rock Identifier

Category

Rock

Browse rock specimens identified by the Rock Identifier community.

Vesicular Basalt with Amygdaloidal Infill (Basalt (Mafic Extrusive Igneous Rock)) — igneous

Vesicular Basalt with Amygdaloidal Infill

Basalt (Mafic Extrusive Igneous Rock)

Basalt (Basalt (extrusive volcanic mafic rock)) — igneous

Basalt

Basalt (extrusive volcanic mafic rock)

Basalt (Vesicular) (Basalt (Extrusive Mafic Igneous Rock)) — igneous

Basalt (Vesicular)

Basalt (Extrusive Mafic Igneous Rock)

River Pebble (Basalt) (Basalt (Aphanitic Mafic Igneous Rock)) — igneous

River Pebble (Basalt)

Basalt (Aphanitic Mafic Igneous Rock)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine or Iron-Stained Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Chert (Jasper variation) (Silicon dioxide (SiO2)) — sedimentary

Chert (Jasper variation)

Silicon dioxide (SiO2)

Concrete Rubble with Aggregate (Hardened Portland Cement Paste with Coarse Aggregate) — Anthropogenic (Man-made)

Concrete Rubble with Aggregate

Hardened Portland Cement Paste with Coarse Aggregate

Anthropogenic (Man-made)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

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

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

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

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Magnetite (Magnetite (Fe3O4)) — mineral

Magnetite

Magnetite (Fe3O4)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Chert (Nodule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Nodule)

Silicon Dioxide (SiO2)

Fire Opal (Common/Precious in Matrix) (Hydrated Silica (SiO2·nH2O)) — mineral

Fire Opal (Common/Precious in Matrix)

Hydrated Silica (SiO2·nH2O)

Sandstone Concretion (Ferruginous Sandstone Concretion (Primarily SiO2 with Iron Oxide cement)) — sedimentary

Sandstone Concretion

Ferruginous Sandstone Concretion (Primarily SiO2 with Iron Oxide cement)

Ferruginous Quartz (Quartz with Iron Oxide inclusions (SiO2 + Fe2O3)) — mineral

Ferruginous Quartz

Quartz with Iron Oxide inclusions (SiO2 + Fe2O3)

Glacial Erratic (Sandstone/Quartzite) (Glacial Erratic specimen (likely Orthoquartzite or Feldspathic Sandstone)) — sedimentary or metamorphic

Glacial Erratic (Sandstone/Quartzite)

Glacial Erratic specimen (likely Orthoquartzite or Feldspathic Sandstone)

sedimentary or metamorphic

Grey Agate (Silicon Dioxide (SiO2) - Variety of Chalcedony) — mineral

Grey Agate

Silicon Dioxide (SiO2) - Variety of Chalcedony

Conglomerate (Conglomeratic Sandstone) — sedimentary

Conglomerate

Conglomeratic Sandstone

Grass (Organic Matter/Soil) (Poaceae (family of monocotyledonous flowering plants)) — Organic Materia (Not a rock or mineral)

Grass (Organic Matter/Soil)

Poaceae (family of monocotyledonous flowering plants)

Organic Materia (Not a rock or mineral)

Quartz Geode Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Garnet-Bearing Schist (Almandine Garnet Micaceous Schist) — metamorphic

Garnet-Bearing Schist

Almandine Garnet Micaceous Schist

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

Chert / Flint

Microcrystalline Quartz (SiO2)

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

Quartz (Milky/Common)

Quartz (Silicon Dioxide, SiO2)

Grey Agate (Tumbled) (Silicon Dioxide (SiO2)) — mineral

Grey Agate (Tumbled)

Silicon Dioxide (SiO2)

Chert (often called Flint in dark varieties) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint in dark varieties)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Chert (Iron-stained) (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (Iron-stained)

Chert (Cryptocrystalline Silica, SiO2)

Chert (Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Desert Rose (Baryte or Gypsum Rose) (Baryte (BaSO4) or Gypsum (CaSO4·2H2O)) — mineral

Desert Rose (Baryte or Gypsum Rose)

Baryte (BaSO4) or Gypsum (CaSO4·2H2O)

Conglomerate (Conglomerate (Clastic sedimentary rock)) — sedimentary

Conglomerate

Conglomerate (Clastic sedimentary rock)

Sandstone with Liesegang Rings (Arenite with Iron Oxide Concretions) — sedimentary

Sandstone with Liesegang Rings

Arenite with Iron Oxide Concretions

Pink Granite (Granite (Felsic Plutonic Rock)) — igneous

Pink Granite

Granite (Felsic Plutonic Rock)

Amygdaloidal Basalt (Amygdaloidal Mafic Volcanic Rock) — igneous

Amygdaloidal Basalt

Amygdaloidal Mafic Volcanic Rock

Granodiorite (Granodiorite (intermediate plutonic rock)) — igneous

Granodiorite

Granodiorite (intermediate plutonic rock)

Quartz Geode (partially formed/chalcedony with iron staining) (Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides) — Mineral/Sedimentary Rock Feature

Quartz Geode (partially formed/chalcedony with iron staining)

Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides

Mineral/Sedimentary Rock Feature

Shale or Mudstone (Based on appearance) (Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)) — Sedimentary

Shale or Mudstone (Based on appearance)

Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)

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

Sandstone

Clastic sedimentary rock (primarily SiO2)

Biotite (Black Mica) (Biotite (K(Mg,Fe++)3AlSi3O10(OH,F)2)) — mineral

Biotite (Black Mica)

Biotite (K(Mg,Fe++)3AlSi3O10(OH,F)2)

Gneiss (Gneiss (High-grade Metamorphic Rock)) — metamorphic

Gneiss

Gneiss (High-grade Metamorphic Rock)

Basalt River Stone (Basalt (Aphanitic Mafic Volcanic Rock)) — igneous

Basalt River Stone

Basalt (Aphanitic Mafic Volcanic Rock)