Limestone, which is a sedimentary rock mainly, composed of crystal forms of calcium carbonate. Around 10% of sedimentary rocks are limestones, which are composed of grains containing skeletal fragments of marine organisms as well as carbonate fragments. The varying color of limestones, especially in weathered surfaces are due to presence of impurities like clay, sand etc. Limestone is used as a building material, as an aggregate for the base of road constructions, and also as an essential component in the production of cement after transforming it into crushed stone.