Mica

Micas are a common group of silicate minerals distinguished by a set of similar chemical and physical properties. Micas are phyllosilicates - they form in thin layers or "sheets". They are a common component of many igneous and metamorphic rocks, including granite, schist, and pegmatites.Significant minerals in the Mica group include Biotite, Muscovite, Lepidolite.

Uses

Mica has been used for a variety of home products, such as insulation, drywall, and roofing. Mica has also been used to add a "shiny" quality to paints. In addition, some minerals in the Mica group are desirable among collectors.

Notable Localities

Mica has been found worldwide in the form of mineral specimens and in metamorphic and igenous rocks.Fine specimens of purple Lepidolite, a Mica mineral, are noted to occur in Brazil. Muscovites are often found in association with  Albite and Aquamarine occur in many Pakistan and Afghanistan pegmatites.

Properties
Chemical FormulaAB2–3(X, Si)4O10(O, F, OH)2
Hardness2-4
Crystal SystemMonoclinic
Mineral ClassSilicates
LusterPearly, Vitreous