I have always maintained that it is not possible to definitively identify a proof striking of a "normal metal" copper or bronze coin from a photograph unless it is totally pristine. We have all seen the same coin portrayed differently according to the conditions and technology used. The exception might be where a proof die is recognisably different from the working dies used to strike circulation coins. And I'm not sure that I've ever seen such a "different" proof striking. Coupled with the fact that there are probably no existing specimens of freshly struck Victorian circulation coins that have been immediately taken out of circulation and preserved in a collection, it is hard to know how close to "proof condition" an early, well-preserved circulation coin might be. Some of the bronzed proofs are clearly identifiable as proofs but probably because they definitely have never seen circulation.
I bid on that 1859 penny at LCA but might have bid higher had I been able to examine it in hand. I did buy an 1860 F6A proof penny from DNW this year but not before I'd discussed its condition with DNW staff and also obtained a guarantee that I could return if not convinced. In hand it has very reflective and "polished" surfaces that satisfy me that it's a proof but photographs just do not capture that aspect.
My 1861 F37 proof penny has very sharp edges and teeth but photos of it don't look particularly proof-like, although Colin Adams, who owned the coin previously, clearly considered it to be a proof.
Bottom line is that you need to look at it in hand and decide for yourself.