I have seen, on occasion, corrosion on a coin form in such a way that the letters were more badly corroded than the background field. When such corrosion is stripped away, the lettering appears as incuse. I have a "modern" (1800s) Australian token where this has happened. The first pic was the coin in the state I received it; the second pic after a wash in concentrated ammonia solution removed the corrosion.


Note particularly the word "SON" in the centre, and the letters "TBU" of "WESTBURY" at the bottom: they've turned incuse. I'm betting a similar process has happened on your coin.


Note particularly the word "SON" in the centre, and the letters "TBU" of "WESTBURY" at the bottom: they've turned incuse. I'm betting a similar process has happened on your coin.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis























