Chalcedony (Agate/Chert variety)
Silicon Dioxide (SiO2)
mineral
Category
Rock
Browse rock specimens identified by the Rock Identifier community.
Serpentinite (often called Jade or Nephrite substitute)
Serpentinite (composed primarily of Antigorite, Lizardite, or Chrysotile)
metamorphic
Quartz (Smoky/Granular variety)
Silicon Dioxide (SiO2)
mineral
Botryoidal Chalcedony (Desert Rose / Agate)
Silicon Dioxide (SiO₂)
Mineral variant
Shale
Shale (clastic sedimentary rock)
sedimentary
Sandstone with Quartz Vein
Arenite with Crystalline Silica (SiO2)
sedimentary
River Pebble (Siltstone / Fine Sandstone)
Sedimentary Rock (siliciclastic clastic rock)
sedimentary
Painted River Rock
Artificially Coated Sedimentary Rock
sedimentary
Basalt (Vesicular or Porphyritic River Pebble)
Mafic Volcanic Rock (Aphanitic to Porphyritic Basalt)
igneous
Greenschist (or Serpentinite) with Quartz-Feldspar Vein
Metabasalt / Greenschist Facies Rock
metamorphic
Quartz pebble
Silicon Dioxide (SiO2)
mineral
Basalt with Calcite Veins
Basalt (containing CaCO3 inclusions)
igneous
Porphyritic Basalt
Porphyritic Basalt (with Plagioclase phenocrysts)
igneous
Basalt
Basalt
Igneous
Quartz Vein in Siltstone
Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix
metamorphic
Porphyritic Basalt
Porphyritic Basalt
igneous
Basalt with Quartz Vein
Basaltic rock with hydrothermal SiO2 filling
igneous
Garnet Schist
Mica Schist with Almandine (Fe3Al2(SiO4)3)
metamorphic
Pumice
Pumice (Amorphous volcanic glass)
Igneous
Porphyritic Basalt (with Pyrolusite or Iron-oxide staining)
Porphyritic Basalt (Mafic Extrusive)
igneous
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Serpentinite
Antigorite, Lizardite, and Chrysotile (Mg3Si2O5(OH)4)
metamorphic
Basalt
Basalt (Mafic volcanic rock)
igneous
Bauxite (Laterite Clay)
Bauxite (mixture of Hydrous Aluminum Oxides: Gibbsite Al(OH)3, Boehmite and Diaspore AlO(OH))
sedimentary
River Stone (likely Basalt or Greywacke)
Basalt with mineral veining
igneous
Unakite
Unakite (altered granite containing Epidote, Orthoclase, and Quartz)
metamorphic
Assorted Beach Rocks and Pebbles
Various (Granite, Basalt, Quartz, Conglomerate, etc.)
igneous, sedimentary, metamorphic
Sandstone
Arenite (primarily SiO2)
sedimentary
Painted Rock / Geode Specimen
Silicon Dioxide with artificial pigment coating
mineral
Dark-colored Igneous Rock (likely Basalt or Diabase)
Basalt (extrusive igneous) or Diabase (intrusive igneous)
Igneous Rock
Sandstone (lithic wacke)
Arenite / Lithic Wacke (mostly SiO2 with rock fragments)
sedimentary
Agate Geode
Silicon Dioxide (SiO2)
mineral
Peach Moonstone
Potassium Aluminum Silicate (KAlSi3O8)
mineral
Conglomerate
Conglomerate rock
sedimentary
Chert (Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2)
mineral
Granite
Granite (Plutonic Igneous Rock)
igneous
Red Sandstone
Arenite (SiO2 with Fe2O3)
sedimentary
Glacial Cobble with Granite Inclusion
Porphyritic Basalt or Andesite containing Granitic Xenolith
igneous
Dalmatian Stone
Dalmatian Jasper (Aplite rock composition)
igneous
Dalmatian Jasper
Peralkaline Quartz-Feldspar Rock with Arfvedsonite
igneous
Sandstone (Wonderstone)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary