Welcome to Treasurenet. That is certainly one cool piece you have found! You will be amazed at the "powers of identification" pulled together in this one handy-dandy forum. However, you can greatly improve the chance of a quick and correct ID by supplying a bit more information to us. I highly recommend reading a "pinned" post by the legendary "PBK" at the top of this forum that provides a few helpful hints. Among them are front and back photos, location found, size, material item is made of, etc. Although someone may recognize this "right off", the more info supplied up-front the easier (and quicker) it will be to ID.
My first thought would be Roman, it does look old. Of course theres also the possibility it is more modern, but made in that same classical style the Romans used. I couldnt tell you anything for certain, though.