Biotite (Mica)
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
mineral
Category
Metamorphic Rock (Composed Of Multiple Minerals)
Browse metamorphic rock (composed of multiple minerals) specimens identified by the Rock Identifier community.
Learn about Metamorphic Rock (Composed Of Multiple Minerals) in the encyclopedia
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Quartz (Small Fragment)
Silicon Dioxide (SiO2)
mineral
Rough Tanzanite
Zoisite (Ca2Al3(SiO4)3(OH))
mineral
Red Granite
Phaneritic Felsic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
mineral
Blue Quartzite (Blue Aventurine / Dumortierite Quartz)
Quartzite with inclusions (SiO2 with AlAl4BSi3O18)
metamorphic
Schist
Mica Schist
metamorphic
Garnet
Garnet group species (likely Almandine, Fe3Al2(SiO4)3)
mineral
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Mineral
Muscovite Mica
Muscovite KAl2(AlSi3O10)(OH)2
mineral
Ferruginous Sandstone (River Pebble)
Clastic Sedimentary Rock (Iron-rich)
sedimentary
Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Magnetite (Iron Ore)
Magnetite (Fe3O4)
mineral
Vesicular Basalt
Vesicular Basalt (Aphanitic-Vesicular Mafic Rock)
igneous
Ferruginous Sandstone
Arenite with Iron-oxide cement
sedimentary
Bauxite Ore
Hydrated aluminum oxides (e.g., Gibbsite Al(OH)3, Boehmite ̲̲̲̲AlOOH, Diaspore ̲̲̲̲AlOOH)
Mineral
Chrysoprase
Chrysoprase (a variety of Chalcedony, SiO₂)
Mineral
US Penny
Cuprum (Copper: Cu) and Zincum (Zinc: Zn) Alloy
Man-made object (metal alloy)
Banded Agate (Polished Slice)
Chalcedony (cryptocrystalline Quartz), SiO2
mineral
Biotite (Mica)
Biotite group (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Shale
Argillite / Shale
sedimentary
Feldspar (Orthoclase)
Potassium Alveolar Silicate (KAlSi3O8)
mineral
Marble
Recrystallized Calcite (CaCO3)
metamorphic
Glacial Cobbles (predominantly Granite and Gneiss)
Mixed lithologies (Quartz, Feldspar, Mica assemblage)
igneous and metamorphic
Chlorite (Small Flakes/Sand)
Chlorite Group (Magnesium Iron Aluminum Silicate Hydroxide - (Mg,Fe)3(Si,Al)4O10(OH)2·(Mg,Fe)3(OH)6)
mineral
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Basalt
Basalt (primarily composed of Plagioclase feldspar and Pyroxene)
igneous
Granite
Granite (composed primarily of Quartz, Feldspar, and Mica)
igneous
Porphyritic Basalt (with Pyrolusite or Iron-oxide staining)
Porphyritic Basalt (Mafic Extrusive)
igneous
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Serpentine
Serpentinite (group of minerals usually (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
metamorphic
Epidote (Unakite-related)
Epidote (Ca2(Al,Fe)3(SiO4)3(OH))
metamorphic
Hypersthene
Hypersthene (formula: (Mg,Fe)SiO3)
mineral
Quartz (various varieties)
SiO₂ (Silicon Dioxide)
Mineral
Sandstone (with Iron Staining)
Clastic sedimentary rock (SiO2 with Fe2O3 oxides)
sedimentary
Massive Quartz
Silicon dioxide (SiO2)
mineral
Quartz (Smoky/Clear variety)
Silicon Dioxide (SiO2)
mineral
Almandine Garnet
Almandine (Fe3Al2Si3O12)
mineral
Magnetite (Iron Ore)
Magnetite (Fe3O4)
mineral
Banded Gneiss and Siltstone River Stones
Gneiss (High-grade Metamorphic Rock)
metamorphic
Quartz
Silicon Dioxide (SiO2)
mineral