Basalt
Mafic volcanic rock (Primarily Plagioclase Feldspar and Pyroxene)
Category
Browse igneous (anthropogenic) specimens identified by the Rock Identifier community.
Basalt
Mafic volcanic rock (Primarily Plagioclase Feldspar and Pyroxene)
Granodiorite
Phaneritic Plutonic Granodiorite
Granite
Granite (Felsic Plutonic Rock)
Granodiorite
Granodiorite (containing quartz, plagioclase, and biotite/hornblende)
Basalt (Weathered/River worn)
Mafic Volcanic Rock (Primarily Plagioclase Feldspar and Pyroxene)
Obsidian
Obsidian (volcanic glass), predominantly amorphous SiO₂
Basalt River Pebble
Mafic volcanic rock (Basalt)
Granodiorite
Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)
Snowflake Obsidian
Obsidian with Cristobalite inclusions (Amorphous SiO2 + SiO2 inclusions)
Basalt
Basalt (Mafic volcanic rock)
Pumice
Pumice (Vesicular Rhyolite/Andesite)
Basalt with vesicles (Amygdaloidal Basalt)
Amygdaloidal Basalt (predominantly Plagioclase and Pyroxene)
Tektite (Indochinite)
Tektite (Amorphous silica-rich impact glass)
Stardust (Micrometeorite)
Chondrite / Micrometeorite (Extraterrestrial Silicate)
Granite
Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)
Obsidian (specifically Silver Sheen Obsidian)
Volcanic Glass (approx. 70–75% SiO2 plus MgO, Fe3O4)
Obsidian (Apache Tear)
Obsidian / Amorphous Volcanic Glass (main component: SiO2)
Basalt with Vesicular Surface
Basalt (Mafic Extrusive)
Granitic Pegmatite (Muscovite and Quartz)
Pegmatite (KAl2(AlSi3O10)(OH)2 / SiO2)
Lunar Meteorite (Feldspathic Breccia)
Achondrite, Lunar Meteorite (Feldspathic Breccia)
Pink Granite (Water-worn Cobble)
Granite (Alkali-feldspar granite)
Basalt
Basalt (Mafic volcanic rock, primarily Plagioclase and Pyroxene)
Feldspar Rich Granite with Limonite Staining
K-Feldspar Granite (KAlSi3O8)
Apache Tear
Obsidian (Hydrated Silica / Amorphous Volcanic Glass)
Porphyritic Basalt with Quartz Inclusions
Aphanitic Porphyritic Basalt
Pegmatite with Muscovite
Granitic Pegmatite (KAl2(AlSi3O10)(OH)2)
Granite (Thin Section)
Granite (Felsic Plutonic Rock)
Diorite (Salt and Pepper Rock)
Diorite
Granite
Phaneritic Granitoid (Primary minerals: Quartz SiO2, Feldspar KAlSi3O8, and Biotite/Mica)
Basalt
Basalt (composition of plagioclase feldspar and pyroxene)
Schorl (Black Tourmaline) in Pegmatite
Sodium Iron Aluminum Borosilicate (NaFe3Al6(BO3)3Si6O18(OH)4)
Granite
Granite (composed primarily of Quartz SiO2, Feldspar KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8, and Mica)
Basalt with Desert Varnish
Mafic Volcanic Rock (Fe/Mg rich Silicate)
Scoria (Lava Rock)
Mafic Volcanic Scoria
Amygdaloidal Rhyolite
Amygdaloidal Rhyolite (Felsic volcanic rock)
Obsidian
Obsidian (Volcanic Glass)
Obsidian
Volcanic Glass (predominantly SiO2)
Basalt with Secondary Mineralization (Likely Zeolites or Calcite)
Aphanitic mafic volcanic rock with secondary mineral inclusions (e.g., CaAl2Si3O10·3H2O for Scolecite)
Basalt
Basalt (Mafic Extrusive)
Granodiorite
Phaneritic Granodiorite
Pink Granite
Granite (Phaneritic intrusive rock rich in K-feldspar)
Granite Cobble
Granite (Felsic Plutonic Rock)