Only the gold, and the silver, the brass, the iron, the tin, and the lead. These are excepted, and, though unclean, are not to be purified by washing, but in another way, by fire, as follows; all these metals were well known in those early times, and were made use of for instruments and vessels of various sorts.
Related Commentaries of Numbers 31:22
Numbers 31:22
22 Only the gold, and the silver, the brass, the iron, the tin, and the lead,