Gneiss
Gneiss (High-grade Metamorphic Rock)
metamorphic
Category
Metamorphic Rock (Primarily Composed Of Minerals)
Browse metamorphic rock (primarily composed of minerals) specimens identified by the Rock Identifier community.
Learn about Metamorphic Rock (Primarily Composed Of Minerals) in the encyclopedia
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Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Sandstone (Pebble)
Arenite (composed primarily of SiO2)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Sandstone
Arenite (Siliclastic sedimentary rock)
sedimentary
Serpentine
Serpentinite (a rock composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite; general formula (Mg, Fe)3Si2O5(OH)4)
metamorphic
Vesicular Basalt (commonly mistaken for Slag)
Scoriaceous Basalt (composed primarily of Plagioclase Feldspar and Pyroxene)
igneous
Weathered quartz-rich rock, likely quartzite or quartz vein fragment
Quartzite, composed predominantly of SiO₂; possible iron-oxide staining
metamorphic
Greenschist (or Serpentinite) with Quartz-Feldspar Vein
Metabasalt / Greenschist Facies Rock
metamorphic
Fuchsite Gneiss or Schist
Muscovite (variety Fuchsite) within Metamorphic Host Rock
metamorphic
Botryoidal Chalcedony (Agate)
Silicon Dioxide (SiO2)
mineral
Sandstone (Red Sandstone)
Arenite (predominantly SiO2 with Fe2O3 cement)
sedimentary
Dalmatian Stone
Dalmatian Stone (a peralkaline igneous rock consisting of Feldspar, Quartz, and Arfvedsonite)
igneous
Slate
Slate; fine-grained metamorphic rock composed mainly of clay minerals, mica, and quartz
metamorphic
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4)
metamorphic
Veined Pebble (likely a Quartz-Veined Pebble)
Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)
Sedimentary Rock (possibly conglomerate or breccia with a quartz vein)
Polished pegmatitic granite (likely graphic granite)
Coarse-grained granitic rock composed chiefly of quartz, feldspar, and biotite/hornblende
igneous
Sandstone
Arenite
sedimentary
Foliated Metamorphic Rock (likely Gneiss or Schist)
Gneissic Metamorphic Rock
metamorphic
Gneissic Granite
Granite Gneiss
metamorphic
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite mica
metamorphic
Granite
Granite
igneous
Sandstone (Quartzose)
Arenite (composed primarily of SiO2)
sedimentary
Sandstone (specifically Arkose or Ferruginous Sandstone)
Sandstone (SiO2 predominant)
sedimentary
Dalmatian Stone
Dalmatian Jasper / Feldspathic Igneous Rock
igneous
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Sandstone (likely Quartzite-rich)
Arenite (primarily SiO2)
sedimentary
Red Shale
Lutite (primarily composed of Hydrous Aluminum Silicates with Hematite staining)
sedimentary
Gneiss
Gneissic Metamorphic Rock
metamorphic
Quartzite
Quartzite (composed primarily of SiO2)
metamorphic
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Sedimentary Rock
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Schist (Greenschist / Mica Schist)
Metamorphic rock rich in platy minerals (e.g., Chlorite/Mica schist)
metamorphic
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
mineral
Green Gneiss
Metamorphic Gneiss
metamorphic
Sandstone
Arenite (primarily composed of SiO2 - Silicon Dioxide)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Granite
Felsic intrusive igneous rock
igneous
Sandstone
Arenite (primarily SiO2)
sedimentary
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Unakite
Altered Granite (composed of orthoclase feldspar, epidote, and quartz)
metamorphic
Ferruginous Sandstone
Arenite with Iron-oxide cement (composed of Quartz and Limonite/Hematite)
sedimentary