I inherited this coin from a friend. Neither of us knows anything about ancient coins, including whether this is even authentic! I think it might be greek in origin. Any thoughts would be appreciated!
To me, although I claim no expertise in this sort of authenticating from simply a photographic image, it looks like it was struck by a machine press. Too perfectly round, with a raised rim on the the reverse. Google that coin, "Tetradrachma of Antioch, Caracalla", and hit "images" for what shape hand struck coins usually took. You might want to look up the weight of what a coin like this should weigh by looking at adds for these coins on the net where sellers often list the weight of the coin. Weigh yours and see whether yours is close to the average. According to "Coinage in the Roman Economy, by Kenneth W. Harl, an excellent book for this sort of thing, a genuine such coin weighs in at 12.94 grams. Please let us know what you discover.
A real one. Note that it looks genuinely ancient. That doesn't always guard against fakes. But a coin that appears "hot off the press" like yours raises immediate red flags.
