Curling stones weigh 44 pounds and originate from a small island off the coast of Scotland. The stones are made from two different types of granite.
According to the New York Times, almost all of the curling stones in the world and all of those used in the Olympics come from an uninhabited 220-acre island just off the coast of Scotland. The stones are common green granite and are cut from the 1,100 foot Aisla Craig that is located on the island. The unfinished stones are then shipped to the mainland to be shaped into proper curling stones. The stones are then attached to a piece of blue hone, another type of granite that creates a seal on the bottom of the stone that is impenetrable by water.