The Gorara stone is used to carve out this beautiful shivling . The craftsmen use chisel and hammer to bring out curved sculpture followed by grinding and polishing. The stone carving shows the intricate craftsmanship of the artisans . Changes colour into black if apply til oil or ghee or full cream milk. This is the shivlingam which is used for home and temple poojan . the fat in milk will make it become black . This Shivling is for purposes only. The shivling shouln't be used without sthapna.