Muscovite

Muscovite or potash mica is the most common and light-colored variety of mica. Its hardness varies from 2 to 2.2 and the specific gravity ranges from 2.8 to 3. Muscovite is chiefly used as an insulator in the manufacture of electrical equipment. India has rich deposits of muscovite in Andhra Pradesh, Bihar and Rajasthan. In all the three places muscovite occurs in pegmatite.