Roman. 2nd century. That's the emperor Hadrian (117-138 AD). From the brassy color of that, I'd say that is a sestertius. Post it on the Ancient Coins forum and you'll likely get more definitive information. Here is one I owned until fairly recently. Yours is lower grade, but as far as I can tell, it doesn't throw up any obvious red flags of being a fake. Looks about right.
