OK, my Dad has been reloading for about 25 years. He gets his lead from tire weights at a guy he knows gas station. Well, that worked for all these years, but now many of the lead tire weights are actually made from some zinc. Does anyone know an easy way to identify what is lead and what is zinc? Is there some simple test? I would think the zinc is harder thus making melting more difficult. But how outside of cutting them open and guessing based on the looks of the metal he doesn't know how to differentiate them. Anybody have a clue?