Crown of silver

Crown of Silver is a colloquial name for psilomelane chalcedony, a variety of chalcedony containing abundant, minute plumes of black manganese arranged in bands. These bands polish to a brilliant, metallic black. Crown of silver is usually sliced and polished for inlays so as to best show the black bands, but can be tumbled or cut cabochon. A typical stone has a base value of 10gp.