I know very little about the coin in question but the rough surfaces make me think it is a cast counterfeit.
Thank you very much for your quick reply, sir. So it seems that the coin is not forging. Bad news for me. Maybe other experts will add some information about it.
Unfortunately I think so too. not sure if its a match for this but found this http://www.forumancientcoins.com/fakes/displayimage.php?album=search&cat=0&pos=29
It looks like a coin copy or "tourist fake" sold to tourists at ancient historical sites. I have a similar one for Lucius Verus which turned up in a movie: