I stopped by a small town park where I live (it is one lot wide and goes back a ways following a stream) which, as far as I can tell is close to where a bank sat 150 years ago. Five minutes into it I was. Heckling out around the base of an old tree and got this hit on the Ace350 coming up as an aggressive ping for a penny. About 4-5 inches deep I found this thing. I have no idea what it might be. It seems to be machined pretty precisely and is the size of a quarter, maybe a touch wider. It is not ferrous.
Any ideas?


Any ideas?

