Possibly Ancient Roman Or Greek, Counterfeit?

Difficult to say if it's real or not. It's badly corroded, looks like it was dipped in acid.

This coin might fit the bill for a "donor" coin in the creation of "spark and chemical erosion dies" (to be used to create forgeries) as described in Wayne Sayles' "Classical Deception" book. I'm certainly not saying that's what we have here, but it is the first thing that crossed my mind. As Sayles describes it, the electrical discharge from the (real) donor coin leaves that coin damaged: "it actually loses...metal in the process...the sacrificial donor electrode gives up part of itself in the transfer process." I've never actually seen such a donor coin after this process, so I could be way off base here...just sharing my 2 cents.