Biotite Mica
K(Mg,Fe)3AlSi3O10(OH)2
Mineral in a matrix (likely quartz or feldspar)
Category
Mineral And Metamorphic Rock
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Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3(Si, Al, Fe)2O5(OH)4
metamorphic
Quartz pebble
Silicon Dioxide (SiO2)
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Tiger Iron
Composite rock (Quartz, Tiger's Eye, Hematite, and Jasper)
metamorphic
Iron-Stained Quartzite
Recrystallized Meta-Quartzite (primarily SiO2)
metamorphic
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz (on matrix)
Quartz (Silicon Dioxide, SiO₂)
Mineral
Biotite Schist
Biotite Mica Schist
metamorphic
Feldspathic Gneiss
High-grade Metamorphic Rock (Gneiss)
metamorphic
Granite Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Gneiss
High-grade metamorphic rock (Gneiss)
metamorphic
Banded Gneiss (with Quartz Vein)
Gneiss (Metamorphic rock of varying mineralogy)
metamorphic
River Pebble (Gneiss / Granitic Schist)
Metamorphic Rock (Quartz-Feldspar-Mica assembly)
metamorphic
Greenstone or Epidote-rich Metamorphic Rock
Chlorite/Epidote Schist or Greenstone
metamorphic
Milky Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
Mineral
Garnet in Schist/Gneiss Matrix
Almandine (Fe3Al2(SiO4)3) or Pyrope (Mg3Al2(SiO4)3)
metamorphic
Quartz (Milky/Bull Quartz)
Silicon Dioxide (SiO2)
mineral
Granite / Gneiss Complex
Felsic Plutonic Rock (Granite) or High-grade Metamorphic Rock (Gneiss)
igneous/metamorphic
Likely quartz-rich mineral fragment
Quartz (SiO₂), possibly iron-stained or included quartz
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Mica Schist
Mica Schist (varies based on mineral makeup, often Biotite/Muscovite schist)
metamorphic
Schist with Quartz/Mica
Mica Schist (primarily Muscovite and Quartz)
Metamorphic
Agate
Silicon Dioxide (SiO2)
mineral
Mica Schist
Crystalline Schist (often containing Muscovite, Biotite, and Quartz)
metamorphic
Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Gneiss
Gneiss (High-grade Metamorphic Rock)
metamorphic
Slate
Foliated Metamorphic Rock (composed primarily of Quartz, Muscovite, and Illite)
metamorphic
Gold-bearing Quartz Vein in Mafic Rock
Hydrothermal Quartz Vein within Greenschist/Amphibolite facies (SiO2 with Au)
metamorphic
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Serpentinite (with Pyrite/Garnet inclusions)
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3Si2O5(OH)4
metamorphic
Black Tourmaline (Schorl)
Schorl (Sodium iron silicate hydroxide boron silicate); NaFe3Al6(BO3)3Si6O18(OH)4
mineral
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)
mineral
Gneiss
Gneiss
metamorphic
Cloud Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Mica Schist with Biotite or Muscovite
Metamorphic rock rich in sheet silicates
metamorphic
Greenstone / Greenschist
Greenschist (composed of Chlorite, Epidote, Actinolite)
metamorphic
Epidosite
Epidosite (composed primarily of Epidote and Quartz)
metamorphic
Biotite Gneiss
Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)
metamorphic
Metagabbro / Epidote Gneiss
Epidote bearing Hornblende Gneiss
metamorphic