how much does a curling stone weigh

A standard curling stone weighs between 38 and 44 pounds, which is about 17.24 to 19.96 kilograms, including the handle.
Most club and Olympic-style stones are near the upper end of that range, often around 42–44 pounds (about 19–20 kilograms), so they feel quite heavy to lift but slide smoothly on the ice.