Granitic Gneiss
Gneiss (Metamorphic rock predominantly containing quartz, K-feldspar, and plagioclase)
metamorphic
Category
Mineral And Metamorphic Rock
Browse mineral and metamorphic rock specimens identified by the Rock Identifier community.
Learn about Mineral And Metamorphic Rock in the encyclopedia
View all →
Greenstone / Greenschist
Greenschist (composed of Chlorite, Epidote, and Actinolite)
metamorphic
Gneiss
Gneiss
metamorphic
Likely weathered quartz-bearing rock fragment
Indeterminate; appears to contain quartz (SiO₂) with iron-oxide staining, possibly from quartzite, granite, or pegmatite
mineral
Blue Topaz
Al2SiO4(F,OH)2
gemstone
Gneiss
High-grade Metamorphic Gneiss
metamorphic
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Schist
Mica Schist (Group of medium-grade metamorphic rocks)
metamorphic
Blue Quartzite
Metamorphosed Quartz (SiO2) with inclusions
metamorphic
Gneiss (Metamorphosed Pebble)
Gneiss with Quartz/Feldspar banding
metamorphic
Gneiss
Gneiss
metamorphic
Quartzite
Quartzite (primarily SiO2)
metamorphic
White Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Granitic Pegmatite Intrusion in Host Rock
Pegmatite dike in amphibolite or schist
igneous and metamorphic
Greenstone
Metabasalt / Greenschist facies rock
metamorphic
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals like Antigorite, Lizardite, or Chrysotile)
metamorphic
Gold Ore in Matrix
Native Gold (Au) in Quartz/Host Rock
mineral
Quartzite with Iron Oxide Vein
Metamorphic Quartzite (SiO2 with Hematite/Limonite impurities)
metamorphic
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Mineral
Schist (Chlorite or Mica-rich)
Chlorite Schist
metamorphic
Quartzite
Quartzite
metamorphic
Black Sapphire
Corundum (Al2O3 with iron and titanium impurities)
mineral
Gneiss
Feldspathic biotite gneiss; a high-grade metamorphic rock composed mainly of quartz, feldspar, and mica
metamorphic
Quartz (specifically Citrine or Yellow Quartzite pebble)
Silicon Dioxide (SiO2)
mineral
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
mineral
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)
Mineral
Mica-rich schist
Muscovite–biotite schist, commonly quartz-bearing
metamorphic
Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Large calcite crystal cluster
Calcite (calcium carbonate, CaCO₃)
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz (River Pebble)
Silicon Dioxide (SiO2)
mineral
Serpentinite
Serpentinite
metamorphic
Banded Gneiss River Pebble
Gneiss
metamorphic
Gneiss
Gneiss
metamorphic
Epidote in Matrix (Unakite-like Rock Fragment)
Epidote (Ca2(Al,Fe)3(SiO4)3(OH)) / Altered Metamorphic Pebble
metamorphic
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Likely serpentine (serpentinite) pebbles
Serpentine-group minerals, chiefly antigorite, lizardite, and/or chrysotile; commonly Mg₃Si₂O₅(OH)₄, sometimes containing magnetite, chromite, and minor carbonate minerals
metamorphic
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Quartzite with Iron Inclusions
Quartzite (SiO2) with Hematite/Limonite
metamorphic
Unakite (or Epidote-rich Granite)
Unakite (Metamorphosed Granite consisting of Epidote, Orthoclase, and Quartz)
metamorphic