Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Category
Igneous, Sedimentary, Or Metamorphic (Mineral Based)
Browse igneous, sedimentary, or metamorphic (mineral based) specimens identified by the Rock Identifier community.
Learn about Igneous, Sedimentary, Or Metamorphic (Mineral Based) in the encyclopedia
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Sandstone
Arenite (SiO2 based)
sedimentary
Sandstone
Arenite (SiO2 based)
sedimentary
Mixed Mineral Collection (Quartz, Amethyst, Rose Quartz, Pyrite, etc.)
Mixed Silicates and Sulfides (SiO2, FeS2)
mineral
Sandstone (Red)
Arenite (primarily Quartz, SiO2, with Iron Oxide cement)
sedimentary
Biotite Gneiss
Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)
metamorphic
Sandstone with Manganese Dendrites
Clastic Sedimentary Rock (SiO2 based with MnO2 inclusions)
sedimentary
Biotite Schist
Biotite Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)
metamorphic
Banded Quartzite
Quartzite (primarily SiO2)
metamorphic
Sandstone
Arenite (SiO2 based)
sedimentary
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
mineral
Gneiss (with Granite/Pegmatite Vein)
Foliated Metamorphic Rock (Quartz-Feldspar Gneiss)
metamorphic
Quartz (Milky/Smoky variety on matrix)
Silicon Dioxide (SiO2)
mineral
Native Gold
Native Gold (Au)
mineral
Green Aventurine (or Xiuyan Jade / Serpentine)
Silicon Dioxide (SiO2) with Fuchsite inclusions or Magnesium Silicate
metamorphic
Tumbled orbicular granite or granitic gneiss
Granite, chiefly quartz–feldspar–biotite/amphibole; exact variety uncertain from the image
igneous
Quartz-veined Gneiss
Gneiss with Quartz (SiO2) intrusions
metamorphic
Dark Agate / Chalcedony
Microcrystalline Quartz (SiO2)
sedimentary
Banded Slate or Siltstone with Quartz/Calcite Veins
Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)
metamorphic
Unidentified Rock
Unknown
sedimentary
Gneiss
Gneiss
metamorphic
Epidote with Magnetite/Hematite inclusions
Epidote (Ca2(Al2,Fe3+)(SiO4)3(OH)) with Iron Oxides
mineral
Muscovite Mica
KAl2(AlSi3O10)(OH)2
mineral
Gneiss
Gneiss
metamorphic
Sandstone Pebble
Arenite (SiO2 based)
sedimentary
Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Rock (likely Sedimentary)
Gneiss (Pebble)
Gneiss
metamorphic
Epidote
Epidote (Ca2(Al,Fe)3(SiO4)3(OH))
mineral
Magnetite
Magnetite (Fe3O4)
mineral
Greenschist
Greenschist (Chlorite-Epidote-Actinolite Schist)
metamorphic
Sandstone with Quarzite clasts
Arenite (SiO2 based)
sedimentary
Anthracite Coal
Anthracite (Carbon-based sedimentary-metamorphic rock)
metamorphic
Epidote
{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
mineral
Amphibolite / Biotite Schist
Amphibolite (rich in Hornblende and Plagioclase feldspar)
metamorphic
Gneiss (High-grade Metamorphic Rock)
Gneiss
metamorphic
Clear Quartz
SiO2 (Silicon Dioxide)
gemstone
Bornite
Bornite (Cu5FeS4)
mineral
Sandstone
Arenite (SiO2 based)
sedimentary
Biotite on Quartz
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2) and Quartz (SiO2)
mineral
River Stone (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) based metamorphosed sandstone
metamorphic or sedimentary
Polished orbicular granite (likely larvikite or orbicular diorite)
Quartz/feldspar-bearing granitoid with dark amphibole–biotite minerals; exact variety requires testing
igneous