Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Category
Browse metamorphic rock (composed of multiple minerals) specimens identified by the Rock Identifier community.
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Granite
Granite (Phaneritic intrusive igneous rock)
Sandstone
Arenite (Sedimentary rock composed of sand-sized grains, primarily SiO2)
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
Greenstone
Greenschist / Meta-basalt
Greenstone
Metabasalt / Chlorite-Epidote Schist
Unakite
Unakitized granodiorite / Quartz-Epidote-Feldspar rock
Blue Quartzite
Quartzite (primarily SiO2 with inclusions)
Blue Quartzite
Metamorphosed Quartz (SiO2) with inclusions
Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
Granite
Granite
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Unakite
Unakite (altered granite)
Blue Quartz (Dumortierite Quartz)
SiO2 containing inclusions of Dumortierite [Al7(BO3)(SiO4)3O3]
Sandstone (River Cobble)
Sandstone (primarily composed of silica, SiO2)
Granite
Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica)
Massive Quartz with Host Rock
Silicon Dioxide (SiO2)
Granite
Granite (Phaneritic Acidic Igneous Rock)
Granite
Granite (composed of Quartz, Alkali Feldspar, and Plagioclase)
Nephrite Jade
Nephrite
Granite
Granite (Phaneritic igneous rock)
Granitoid (Commonly Granite)
Phaneritic Felsic Igneous Rock
Biotite Schist
Biotite Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)
Greenstone (Greenstone River Pebble)
Greenschist (metamorphosed mafic igneous rock)
Gneiss
Gneiss
Sandstone
Arenite (SiO2 principal)
Schist
Mica Schist
Mica Schist
Mica Schist (primarily Muscovite and Quartz)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Gneiss (with Quartz and Biotite Mica)
Gneiss
Granite
Granite (Phaneritic Igneous Rock)
Kyanite
Kyanite (Al2SiO5)
Greenstone
Metabasalt / Chlorite Schist
Blue Quartzite (Dyed)
Metamorphosed Quartz-rich Sandstone (SiO2 with organic dye)
Yellow Quartzite Pebble
Quartzite (primarily Silicon Dioxide - SiO2)
Green Aventurine (Green Quartzite)
Silicon Dioxide (SiO2) with inclusions of Fuchsite mica
Sandstone
Arenite (primarily SiO2)
Serpentine
Antigorite, Lizardite, or Chrysotile; (Mg, Fe)3Si2O5(OH)4
Unakite
Epidotized Granite
Basalt (River Pebble)
Basalt
Sandstone
Sandstone (arenite is a more specific geological term for a clean sandstone, while wacke refers to a dirty sandstone with significant matrix)