Coin hunting is looking for pre 1964 dimes quarters or half dollars. They were made with 90 percent silver. 1965 to 1969 half dollars have 40 percent silver. I ask the banks if they have any half dollars then exchange cash for however many they have. We look through them pull out all the ones with silver and take the rest back to the bank to get our money back. Not sure about the U.K. You won't get rich doing it but my sons think it is awesome.