Either Roman or an imitation. I hope someone else can read the inscription; I doubt I'd be able to without the coin in hand. How big is the coin?
It looks like this Roman coin of Septimius Severus (AD 193-211) Septimius Severus Denarius RIC 131 (RIC is "The Roman Imperial Coinage", edited by Mattingly, Harold, Sydenham, and others) L SEPT SEV AVG IMP XI PART MAX Laureate head right IOVI PROPVGNATORI Jupiter advancing right, brandishing thunderbolt, cloak twined around left arm http://www.wildwinds.com/coins/ric/septimius_severus/t.html
Pretty close, but the details of the design are different. Not that I have any idea what it is, but I'll look it up later.
