Curling has also become a trending spectator sport during the games with its brooms and curling stones. But what you may not realize is that curlers at the Olympics are very particular about their equipment, especially when it comes to curling stones. What’s So Special About Curling Stones? The granite stones, which weigh between 17.24 and 19.96 kilos or 38 pounds to 44 pounds, come from a small island off Scotland called Ailsa Craig. The island's granite has been specifically used for curling stones because of its remarkable properties that are perfect for curling compared to other types of granite.