The mica group of phyllosilicate minerals are all flat and flaky, which is attributed to their characteristic and almost perfect basal cleavage. This means that instead of shattering into irregular pieces when broken, mica breaks into thin sheets or flakes
Five minerals have the characteristic mica cleavage, including biotite, muscovite, glauconite, margarite and phlogopite. Muscovite is also known as common mica because it is the most abundant of the group, or white mica because of its light-colored appearance. Biotite is another common mineral from the mica group and is known as black mica for its dark coloration. Mica minerals are used extensively as industrial silicates and appear in the beauty industry, the electrical industry and microscopy.