Scotland’s Ailsa Craig Island and the Granite for Olympic Curling Stones

And with the Winter Olympics coming up, a Scottish island has already taken a place on the podium for its dense granite. The rock's natural elasticity and resistance to cracking makes it ideal for one of the most famous sports at the games. NTD's Andrew Thomas has more on the stones. >> Welcome to Elsa Craig. 10 miles off Scotland's west coast, the uninhabited island is made almost entirely of micro granite. The dense and durable rock is central to Olympic curling. Jim English says two types of granite are found here. >> This stone is in common green and this is used for the body of the stone. There's like an elasticity property in the stone itself which allows it to be struck all the time on the ice with other stones. So that's used as a body of the stone. >> Both are used to make curling stones. Curlers push the heavy polished granite discs across ice toward a target using brooms to guide their path. Both types of stone are found on different parts of the remote island. >> You know, there's virtually no human disturbance. Um, which does pose a a slight um extra constraint with the works here and that we are bringing that human disturbance, but um with working with case, we we're always very careful. >> No one lives on Elsa Craig. That makes it a thriving habitat for seabirds and gray seals. Ecologist Harry Fischer says workers strive to keep it that way. two different types of material a Craig that we want to use is blue horn material which forms the running surface of the color stone a common green which forms the body of the stone. Um this product common green can be found at the southern end of the island and the blue horn can be found at the northern end of the island. >> Granite harvesting on the island happens roughly every 5 years. The process requires a license and is only permitted in certain areas. Once gathered, a boat transports the boulders back to the Scottish mainland. Jim's son, Ricky English, shows off the final product. >> Your typical Culling stone that we produce here at the factory. It's made up of the Ela Craig common green, which you see here is the body of the curling stone. And why we use this product for the body of Culling Stone because the granite itself has got like elasticity properties in it. >> K's Curling has been making curling stones since 1851. English points out how the distinct details make an impact in the sport. >> You see these we black speckles here. These are called like felt spars. So when the two stones collide together on impact, this basically absorbs that energy and shoots it out the other end. So the stone doesn't actually split. So it makes it perfect for the the body at Cing Stone. >> K's Curling has supplied every set of stones used in Olympic competition since 1998. The company says it produces between 1,800 and 2,000 stones per year. Andrew Thomas, NTD News.