Recently purchased this 1882 US mint medal, Julian CM-20, guessing it was one of the restikes from the mint produced in the 70's-80's. When I examined the piece under loop I found that it was definitely gilt gold over what I'm 98% sure is copper. I researched but can find no mention of that metal combination existing.

Does any body have further info, comments OR most helpful...if any body has an original copper or a restrike and a scale, knowing the weight would help me at least confirm my thoughts on base metal. Thanks.