5 -Pegmatite 

Hello friends, Welcome to the Rock Repository at the Department of Geology, Shivaji Science College, Nagpur.

I am pegmatite, an Acidic plutonic igneous rock having coarse grained texture. I am formed from waters that separate from a magma in the late stages of crystallization. I contain more than 75% silica in the form of Quartz, K-Feldspar, muscovite and biotite as dominant minerals,along with which Ca-Feldspar and Amphiboles like Hornblende can be observed. In India I am found in south central Rajasthan, Bihar, Jharkhand, Bastar, Odisha,  West Bengal, Assam, Maharashtra etc. I am mainly used to make components for electronic devices, retardation plates, circuit boards, optical filters, detector windows. Thank you for visiting.