Gneiss
Gneiss
Category
Browse sedimentary and metamorphic specimens identified by the Rock Identifier community.
Gneiss
Gneiss
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
Gneiss
Gneiss (High-grade Regional Metamorphism)
Quartzite
Quartzite (consisting primarily of SiO2)
Jasper pebble
Silicon Dioxide (SiO2) with iron oxide impurities
Anthracite Coal
Anthracite
General Gravel (River Rock/River Stones)
Mixed Lithic Sediments (Conglomerate Clasts)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Gneiss (Granitic Gneiss)
Gneiss (composed mainly of quartz, K-feldspar, plagioclase, and biotite)
Banded Gneiss
Gneiss (Metamorphic rock predominantly containing quartz, feldspar, and mica)
Gneissic Granite (River Stone)
Protomylonite or Gneiss
Garnet Schist
Almandine-bearing Mica Schist
Gneiss
Gneiss
Gneiss
Gneiss
Gneiss (specifically a Granitic Gneiss specimen)
Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)
Gneiss (with Quartzite and Biotite)
Gneiss containing SiO2 (Quartz), K(Mg,Fe)3AlSi3O10(OH)2 (Biotite), and (K,Na,Ca)AlSi3O8 (Feldspar)
Mica Schist
Mica Schist (primarily Muscovite and Quartz)
Phyllite
Phyllite
Anthracite Coal
Anthracite
Schist (Micaceous Schist)
Schist (comprising Muscovite/Biotite mica, Quartz, and Feldspar)
Quartzite
Quartzite (SiO2)
Smoky Quartz and Biotite Schist
Quartz-Biotite Schist (SiO2 + K(Mg,Fe)3AlSi3O10(F,OH)2)
River Cobble (Phyllite or Quartzite)
Metasedimentary Rock (often containing SiO2 or KAl2(AlSi3O10)(OH)2)
Banded Gneiss
Foliated Gneiss
Gneiss
Gneiss
Gneiss
Gneiss
Red aventurine
Silicon Dioxide (SiO2) with Hematite/Goethite inclusions
Quartzite with Differential Weathering
Quartzite (SiO2)
Quartzite
Quartzite (composed primarily of Silicon Dioxide, SiO2)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Quartzite
Quartzite (SiO2)
Quartzite
Quartzite (SiO2)
Jasper, Agate, Quartz Mix (Polished Beads)
SiO₂ (Silicon Dioxide) for Quartz. Jasper and Agate are cryptocrystalline varieties of Quartz.
Quartz River Stone
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Dyed Agate
Microcrystalline Quartz (SiO2) with artificial pigment
Sand (Construction Grade)
Unconsolidated siliciclastic sediment (primarily SiO2)
Banded Slate or Siltstone with Quartz/Calcite Veins
Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)
Quartz Pebble
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (SiO2-rich metamorphic rock)
Banded Gneiss
Gneiss (High-grade metamorphic rock)