Mica is a transparent mineral composed of  complex mixtures of potassium silicates. The variety of mica used most frequently by these Indian artists is Muscovite (H₂KAl₃ Si0₄)₃ which is found widely throughout south India. The mica is formed between strata of granite and the transparency of the material is a result of the heat and pressure created between the layers of rock during formation. Mica consists of many interlocking platelets, resulting in a laminar structure which can be split easily  into thin sheets.