Basalt
Extrusive Mafic Igneous Rock (composed primarily of plagioclase feldspar and pyroxene)
Category
Browse igneous rock specimens identified by the Rock Identifier community.
Basalt
Extrusive Mafic Igneous Rock (composed primarily of plagioclase feldspar and pyroxene)
Granite (likely a river or beach pebble)
Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)
Vesicular Basalt
Extrusive Mafic Igneous Rock (composed of Plagioclase feldspar, Pyroxene, and Olivine)
Basalt
Extrusive Mafic Igneous Rock (composed primarily of plagioclase, pyroxene, and olivine)
Basalt
Extrusive Mafic Igneous Rock (composed primarily of Plagioclase, Pyroxene, and Olivine)
Dalmatian Stone
Dalmatian Stone (a peralkaline igneous rock consisting of Feldspar, Quartz, and Arfvedsonite)
Granodiorite
Granodiorite (containing Quartz, Plagioclase Feldspar, Biotite, and Hornblende)
Peridotite (with Olivine)
Peridotite (dominantly (Mg, Fe)2SiO4)
Quartz (Smoky/Granular variety)
Silicon Dioxide (SiO2)
Granite
Phaneritic Acidic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Basalt with Quartz Veins
Aphanitic Mafic Igneous Rock (primarily Plagioclase and Pyroxene) with SiO2 inclusions
Pink Granite
Phaneritic intrusive igneous rock with Potassium Feldspar (KAlSi3O8) and Quartz (SiO2)
Pumice
Pumice (a highly vesicular extrusive igneous rock, primarily amorphous silica)
Granite
Phaneritic Plutonic Igneous Rock (composed of quartz, alkali feldspar, and plagioclase)
Granite Pebble
Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)
Granite
Phaneritic Plutonic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Pumice
Pumice (Highly vesicular felsic extrusive igneous rock; primarily SiO2)
Chrysocolla in Matrix
Hydrated copper phyllosilicate (Cu,Al)2H2Si2O5(OH)4' nH2O on Quartz/Feldspar matrix
Ocean Jasper
SiO2 (Silicon Dioxide) - Chalcedony variety
Granodiorite
Granodiorite
Granite with Quartz Vein
Phaneritic Felsic Igneous Rock (composed of Quartz [SiO2], Feldspar, and Mica)
Eucrite Meteorite
Achondrite (Eucrite)
Basalt with Quartz Vein
Basalt (fine-grained mafic igneous rock) with crystalline Quartz (SiO2)
Granite Cobble
Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Granite (Weathered)
Phaneritic Felsic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Basalt
Basalt
Granite with Epidote
Granite, containing quartz, feldspar, and epidote
Diorite (Salt and Pepper Rock)
Phaneritic plutonic igneous rock (sodium-rich plagioclase feldspar and hornblende)
Snowflake Obsidian
Vitreous volcanic rock with Cristobalite inclusions (mostly SiO2)
Dragon Vein Agate (Dyed)
SiO2
Obsidian
Volcanic Glass (SiO2)
Black Obsidian
Volcanic Glass (SiO2 + impurities)
Granite
Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica)
Granite Pebble
Intrusive Felsic Igneous Rock (primarily SiO2 with Al2O3, K2O, Na2O)
Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
Granite
Phaneritic Igneous Rock (composed mostly of Quartz, Alkali Feldspar, and Plagioclase)
Granite
Plutonic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)
Red Granite
Phaneritic Felsic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz and Alkali Feldspar)
Granite
Phaneritic Intrusive Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
Granite Pebble (Salt and Pepper Granite)
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Biotite/Amphibole)