Basalt
Basalt (Mafic volcanic rock)
Category
Browse igneous rock (volcanic glass) specimens identified by the Rock Identifier community.
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (Mafic volcanic rock)
Andesite Porphyry
Andesite (Intermediate Volcanic Rock)
Basalt
Basalt (Mafic volcanic rock)
Porphyritic Basalt (Leopard Rock)
Porphyritic Mafic Volcanic Rock
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (Mafic volcanic rock)
Andesite
Andesite (intermediate volcanic rock)
Basalt
Mafic volcanic rock (Basalt)
Vesicular Basalt (Iron-Stained)
Mafic Volcanic Rock (Basalt)
Porphyritic Basalt (Peanut Obsidian/Star Galaxy-style)
Porphyritic Basalt (Silica-rich Volcanic Rock)
Basalt with Iron Oxidation
Mafic Igneous Basalt
Basalt
Basalt
Scoria (Vesicular Basalt)
Scoria (Extrusive Igneous Rock)
Basalt River Stone
Basalt (Aphanitic Mafic Igneous Rock)
Granite
Granite (Felsic Plutonic Rock)
Druzy Quartz
Silicon Dioxide (SiO2)
Basalt with Quartz Veining
Basalt (Mafic Extrusive Igneous Rock) with SiO2 (Silicon Dioxide) veins
Basalt with Plagioclase Phenocrysts (Porphyritic Basalt)
Porphyritic Basalt (primarily Plagioclase Feldspar, Pyroxene, and Olivine)
Basalt
Extrusive mafic igneous rock
Basalt
Afanitic Mafic Basalt
Scoria (Lava Rock)
Scoria (Extrusive Igneous Rock / Mafic Silicates)
Scoria (Lava Rock)
Mafic Volcanic Scoria
Basalt
Basalt
Basalt with Plagioclase Phenocrysts
Porphyritic Basalt
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Olivine (Peridotite)
(Mg, Fe)2SiO4 (Magnesium Iron Silicate)
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Scoria (Lava Rock)
Scoria
Basalt (with possible weathering or secondary mineral crust)
Basalt (Aphanitic Mafic Igneous Rock)
Basalt
Aphanitic Mafic Igneous Rock
Vesicular Basalt (or Scoria)
Basalt (Aphanitic-Vesicular Mafic Igneous Rock)
Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)
Quartz (SiO₂)
Peridot in Basalt/Xenolith
Olivine (Mg, Fe)2SiO4 in Vesicular Basalt
Grey Agate
Silicon Dioxide (SiO2) - Variety of Chalcedony
Muscovite Mica (Golden/Yellow variety)
KAl2(AlSi3O10)(F,OH)2
Basalt
Extrusive mafic igneous rock
Scoria (Vesicular Basalt)
Scoria (Extrusive Igneous Rock)
Basalt
Extrusive mafic igneous rock