Mica (specimen appears to be Muscovite or Phlogopite)
Phyllosilicate mineral; Muscovite: KAl2(AlSi3O10)(F,OH)2
Mineral (Found in Igneous and Metamorphic rocks)
Category
Metamorphic Rock (Primarily Composed Of Minerals)
Browse metamorphic rock (primarily composed of minerals) specimens identified by the Rock Identifier community.
Rough Star Sapphire (Corundum)
Al2O3 (Aluminum Oxide)
mineral
Quartz (Pale Rose or Milky Variety)
Silicon Dioxide (SiO2)
mineral
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
mineral
Garnet
Almandine (Fe3Al2(SiO4)3)
mineral
Septarian Nodule (Dragon Stone) sphere
Septarian concretion (Calcite, Aragonite, and Limestone)
sedimentary
Clear Quartz Sphere
Quartz (Silicon Dioxide, SiO2)
mineral
Lazulite
Magnesium Aluminum Phosphate Hydroxide (MgAl2(PO4)2(OH)2)
mineral
Limestone (specifically Travertine or Tufa)
Calcium Carbonate (CaCO3)
sedimentary
Quartz (Milky or Common Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz (Common or Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz Geode
Silicon Dioxide (SiO2) within a geode
mineral
Jade (likely Nephrite or Jadeite)
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)
Mineral
Granite
Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8), and Mica)
igneous
Ferruginous Conglomerate
Conglomerate with Iron-Oxide Matrix (SiO2 + Fe2O3/FeO(OH))
sedimentary
Pink Granite
Phaneritic intrusive igneous rock (K-feldspar rich)
igneous
Chinese Writing Stone
Porphyritic Basalt or Porphyritic Andesite with Feldspar phenocrysts (SiO2-rich Silicates)
igneous
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2) with various iron-oxide inclusions
mineral
Lapis Lazuli
Lapis Lazuli (a rock, not a single mineral; primary mineral is Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
Metamorphic rock
Yellow Quartzite
Quartzite (primarily Silicon Dioxide - SiO2)
metamorphic
Red Quartzite (Tumbled Pebble)
Quartzite (primarily SiO2 with hematite inclusions)
metamorphic
Red Quartzite River Pebble
Quartzite (SiO2 with iron oxide inclusions)
metamorphic
Unakite (or Epidotized Granite)
Epidotized Granite (Composition: KAlSi3O8, Ca2(Al,Fe)3(SiO4)3(OH), SiO2)
metamorphic
Greenstone / Diorite
Intermediate plutonic igneous rock
igneous
Stiped Slate Beach Pebble
Low-grade Metamorphic Slate with Quartz Vein (SiO2 on Phyllosilicate base)
metamorphic
Agate
Silicon Dioxide (SiO2)
mineral
Amygdaloidal Basalt with Quartz/Calcite Inclusions
Amygdaloidal Basalt (SiO2 / CaCO3 inclusions)
igneous
Lapis Lazuli
Lapis Lazuli (Complex silicate rock containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Pyrite, and Calcite)
metamorphic
Red Sandstone
Arenite
sedimentary
Quartz (Milky/Bull Quartz)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartzite
Quartzite (Primary mineral: SiO2)
Metamorphic
Marble (Calcitic)
Metamorphosed Limestone (CaCO3)
metamorphic
Black Tourmaline (Schorl)
Schorl (Sodium iron silicate hydroxide boron silicate); NaFe3Al6(BO3)3Si6O18(OH)4
mineral
Sandstone (Painted)
Arenite (primarily SiO2)
sedimentary
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Quartz
SiO₂ (Silicon Dioxide)
Mineral
Staurolite (Fairy Cross)
Staurolite (Fe2+2Al9Si4O23(OH))
metamorphic
Quartz Druzy Geode
Silicon Dioxide (SiO2) - Crystalline Variety
mineral
Rhodonite in Matrix
Rhodonite (Manganese Silicate) - (Mn2+,Fe2+,Mg,Ca)SiO3
mineral
Granitic Pegmatite
Granitic Pegmatite (principally Quartz, Potassium Feldspar, and Mica)
igneous
Sandstone
Arenite (SiO2 primarily)
sedimentary