Porphyritic Basalt
Porphyritic Basalt (with Plagioclase phenocrysts)
Category
Browse sedimentary or igneous specimens identified by the Rock Identifier community.
Porphyritic Basalt
Porphyritic Basalt (with Plagioclase phenocrysts)
Olivine (Peridotite)
Magnesium iron silicate (Mg, Fe)2SiO4
Snowflake Obsidian
Volcanic Glass with Spherulite inclusions (Chemical composition: 70–75% SiO2 + MgO, Fe3O4)
Porphyritic Basalt (Leopard Rock)
Porphyritic Mafic Volcanic Rock
Granite
Granite (Felsic Plutonic Rock / SiO2 + Al2O3)
Yooperlite (Sodalite-bearing Syenite)
Sodalite-rich Syenite
Granodiorite
Phaneritic-textured Intrusive Granodiorite
Porphyritic Rhyolite (Red Porp)
Porphyritic Rhyolite (Felsic volcanic rock)
Basalt (Lava Rock) and Dyed Glass/Quartz
Scoria (Vesicular Basalt)
Basalt
Vesicular Basalt
Granite
Phaneritic Plutonic Rock (primarily Quartz, Feldspar, and Mica)
Granodiorite Core
Granodiorite
Basalt
Mafic Volcanic Rock (composed mainly of Plagioclase, Pyroxene, and Olivine)
Pink Granite
Granite (Alkali-feldspar granite)
Scoria (Red Lava Rock)
Scoria (Vesicular basaltic rock)
Amygdaloidal Basalt
Amygdaloidal Basalt with Secondary Infilling (e.g., Agate, Quartz, or Zeolite)
Red Granite
Felsic Plutonic Rock (Granite)
Granitic Pegmatite
Pegmatite (Quartz: SiO2, Feldspar: KAlSi3O8, Mica: KAl2(AlSi3O10)(OH)2)
Basalt Pebble
Aphanitic mafic volcanic rock
Diorite
Diorite (Intermediate plutonic rock)
Basalt
Basalt (Mafic volcanic rock)
Scoria (Lava Rock)
Scoria (extrusive volcanic rock)
Obsidian
Volcanic Glass (Amorphous Silica)
Peridotite (Olivine/Peridot)
Peridotite: (Mg,Fe)2SiO4 (Olivine-rich ultramafic rock)
Obsidian
Volcanic Glass (70-75% SiO2)
Granite Pebble
Granite (Felsic Plutonic Rock)
Obsidian
Obsidian (Volcanic glass), SiO2 (major component)
Granite
Phaneritic Plutonic Felsic Rock (KAlSi3O8 + SiO2 + NaAlSi3O8)
Chondrite Meteorite
L3 Chondrite (Unequilibrated Ordinary Chondrite)
Black Obsidian
Volcanic Glass (SiO2)
Basalt (River Cobble)
Basalt (Mafic volcanic rock)
Green Porphyry (Flowerstone)
Porphyritic Andesite or Basalt
Basalt
Basalt (Composition primarily Plagioclase feldspar, Pyroxene, and Olivine)
Lava Rock (Scoria)
Extrusive basaltic scoria
Scoria (Red Lava Rock)
Scoria (Vesicular Basalt/Andesite)
Basalt (Gravel Pebble)
Basalt (contains pyroxene, plagioclase feldspar, and olivine)
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide, SiO2)
Andesite River Stones
Andesite
Basalt with Magnetite inclusions
Basalt (Mafic silicate rock) potentially containing Magnetite (Fe3O4)
Scoria
Vesicular Basalt / Scoriaceous Basalt
Basalt with inclusion
Basalt (Aphanitic-Porphyritic texture)
Snowflake Obsidian
Volcanic glass with Spherulite inclusions (SiO2)