I crh'ed some halves a week ago and found a 1973 D Half. Sounds normal right? Its not it looks like it is stamped on a proof blank. Same shinyness, but its not cameo at all. Is that valuable? Never seen it before.
To me it sorta looks plated, though it could just be the picture
Either way its a nice looking coin But as far as I'm aware the Denver mint wouldn't have the technology to make proofs, it could just be a really nice coin, either way, I'd stick that in a 2x2
it does look rather shinny. Someone else posted earlier today finding a '74 half that looks silver plated with a silver rim. I'd say it's worth keeping at least till you can get some expert opinions on it and if nothing else just keeping as a novelty coin.