Basalt River Cobble
Basalt (Mafic Igneous Rock)
Category
Browse sedimentary (base), then artificial specimens identified by the Rock Identifier community.
Basalt River Cobble
Basalt (Mafic Igneous Rock)
Basalt
Basalt (composition of Plagioclase feldspar and Pyroxene)
Amygdaloidal Basalt
Basalt with secondary amygdule minerals (likely Epidote or Chlorite)
Basalt with Quartz/Quartzite Veins
Aphanitic Mafic Volcanic Rock with Siliceous Infillings
Basalt
Basalt (Mafic Extrusive Rock)
Pink Granite
Granite (Felsic Plutonic Rock)
Granodiorite (Water-worn Pebble)
Granodiorite
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Granite (specifically Pink or Alkali Feldspar Granite)
Felsic Plutonic Rock (primarily SiO2 with KAlSi3O8)
Granite
Phaneritic Felsic Igneous Rock
Basalt
Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
Porphyritic Basalt (with Quartz or Calcite inclusion)
Porphyritic Basalt (Matrix: SiO2/MgO/FeO, Phenocryst: likely Quartz or Calcite)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Greenstone / Diorite
Intermediate plutonic igneous rock
Basalt
Extrusive mafic volcanic rock
Basalt
Basalt (composition mainly of Plagioclase feldspar, Pyroxene, and Olivine)
Greenstone
Metabasalt / Chlorite-Epidote Schist
Granite
Granite (Felsic Plutonic Rock)
Basalt (River Pebble)
Extrusive mafic igneous rock
Pink Granite
Phaneritic Felsic Igneous Rock (composed primarily of K-Feldspar, Quartz, and Plagioclase)
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
Gabbro
Plutonic mafic rock
Quartzite (or Milky Quartz pebble)
Quartzite (Metamorphosed Sandstone) / Silicon Dioxide (SiO2)
Granite
Phaneritic Plutonic Igneous Rock (primarily composed of quartz, alkali feldspar, and plagioclase)
Basalt (River Stone)
Basalt
Granite
Granite (composed primarily of Quartz SiO2, Potassium Feldspar KAlSi3O8, and Plagioclase)
Granite
Granite (Phaneritic igneous rock)
Granite
Phaneritic plutonic felsic rock (Quartz, Feldspar, Mica)
Basalt
Extrusive mafic igneous rock
Basalt
Basalt (Mafic volcanic rock)
Andesite
Andesite (Intermediate Volcanic Rock)
Granite
Phaneritic Plutonic Felsic Rock (KAlSi3O8 - SiO2 - NaAlSi3O8)
Basalt
Extrusive mafic igneous rock
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Basalt
Basalt
Granite
Granite (Phaneritic igneous rock)
Granite
Granitoid (composition typically SiO2, Al2O3, K2O, Na2O)
Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz and Alkali Feldspar)
Granite
Plutonic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Granite (with Orthoclase and Quartz)
Phaneritic Felsic Igneous Rock (KAlSi3O8 + SiO2)
Diorite
Intermediate plutonic igneous rock
Basalt Pebble
Vesicular Basalt