The inside cup holds a 5-inch running diameter.
Wear is mostly inwards on a curling stone.
If the stones are not highly polished the granite has a course texture, allowing moisture to penetrate the stones, causing premature pitting. The type of granite from which stones are manufactured will also determine the life expectancy of the stones. Stone reconditioners such as Canada Curling Stone Co. recondition club stones to the same shapes and dimensions as new curling stones. The old running surface of stones is refurbished by recupping and regrinding the entire bottom of the stone. These stages of reconditioning are done by machine, ensuring proper cup depth.