Mica is a group of silicate minerals that have a layered structure. This structure allows the mineral to be easily split into thin, flexible sheets.

Some common types of mica include:

* Muscovite: A silvery-white mica often used in insulation and makeup.

* Biotite: A black or dark brown mica commonly found in igneous rocks.

* Phlogopite: A yellowish-brown mica used in electrical insulation.

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