Gneiss
Gneiss
Category
Browse mineral, specifically a rock fragment specimens identified by the Rock Identifier community.
Gneiss
Gneiss
Lapis Lazuli
Complex rock primarily containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2
Quartz / Quartzite
Quartz (Silicon Dioxide, SiO2)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Dalmatian Stone (commonly Dyed)
Dalmatian Jasper (Peralkaline igneous rock)
Man-made Synthetic Material (Plastic/Composite)
Acrylonitrile Butadiene Styrene (ABS) or High-Impact Polystyrene (HIPS)
Greenstone with Quartz Veining
Epidiorite or Metabasalt with SiO2 (Quartz) veins
Granite
Granite (Felsic Plutonic Rock)
Basalt with Iron Oxidation
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Basalt
Basalt
Granite
Granite (Mainly Quartz SiO2 and Feldspar KAlSi3O8)
Amygdaloidal Basalt
Amygdaloidal Basalt
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Blue Howlite (Dyed)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Milky Quartz
Silicon Dioxide (SiO2)
Druzy Quartz (on Quartzite or Chert)
Silicon Dioxide (SiO2)
Granite / Gneiss Complex
Felsic Plutonic Rock (Granite) or High-grade Metamorphic Rock (Gneiss)
Olivine in Basalt matrix
Peridotite (Mg, Fe)2SiO4
Schist
Mica Schist
Jasper
Silicon dioxide / Chalcedony (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Iron-Stained Quartz (Riverside Cobble)
Silicon Dioxide (SiO2) with Limonite/Hematite inclusions
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Quartz Pebble (Iron-stained)
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
White Chalcedony (likely Common Opal or Milky Quartz)
Silicon Dioxide (SiO2)
Quartz with Iron Oxide Monzonite or Sandstone contact
Quartz (SiO2) with Limonite/Hematite staining
Quartz / Quartzite
Silicon Dioxide (SiO2)
Epidote (or Epidote-rich rock)
Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Granodiorite
Granodiorite (Intermediate intrusive igneous rock)
Ferruginous Quartz
Quartz (Silicon Dioxide) with Iron Inclusion, SiO2
Granite
Phaneritic Igneous Rock (Granitic)
Sandstone (Ferruginous Concretion)
Ferruginous Sandstone Concretion / SiO2 with Fe2O3 cement
Pyrite (on Quartz/Host Rock)
Iron Sulfide (FeS₂)
Limonitic Iron Ore / Goethite
Hydrated Iron(III) oxide-hydroxide (primarily FeO(OH)·nH2O)
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
Basalt
Basalt
Biotite Mica in Host Rock
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Sandstone (clastic)
Clastic Sedimentary Rock (primarily composed of SiO2)