Hello I am just wondering why these two identical coins of Leo III with Constantine V have different colors? It doesn’t appear to me that one of them is better “cleaned”, so why is one green while the other is black? And something else: Do you think the two coins are Sear 1516 BOTH of them? The seller has labeled them so but I have trouble: Because the legends on the green one says: “LEON SC ONSTA”, but on the black one the last letters only says “OU” where I was expected to see a “ST”? It is not clear to me whether the black coin indeed does have “OU” or whether the letters have eroded? Can anyone cut the Gordian knot?
Bronze can develop a variety of differing patinas, depending on its environmental history. The thing is, these coins are not identical, no two ancient (or Byzantine) coins are, in the sense that modern coins can be identical. They are not die matches, their flans are of different shapes, and they likely share very different histories. The second does look like it was over-cleaned. Proper cleaning does not break through the patina to the underlying raw bronze.
@stevex6 Just for clarification I only own the green one, not both. - But thanks. I never trumpet about my byzantine coins