The easiest way to clean silver or billon finds is to use Cleanbill. Just pour 2 drops of Cleanbill on the find. Use a brass brush doing circulat movements. Get rid of the mud and liquid, then rinse. Use a microfiber fabric to make it shine. If necessary renew operation. Cleanbill also works very nicely on modern alloys. See an example in the following video:
mars 22, 2018