"New style" Athens tetradrachm. Better images, weight, and diameter are needed to help authenticity but from what I can see it appears to be authentic. Better images would also help with determine condition and value, but it is in the ballpark of ~$200. Attribution: Attica, Athens Circa 157-156 BCE AR New Style Tetradrachm Obverse: Helmeted head of Athena right Reverse: A - ΘΕ; EV/MH EΠI/ΓEN/ΣΩΣΑN/DΡOΣ, Owl on amphora; eagle on thunderbolt left Reference: Thompson 447d The reverse legend shows the names of the magistrates under whom the coin was issued (there are many different magistrates and variations). AΘΕ = abbreviation for Athens.
I have no knowledge but TIF is probably correct. Repost in the Ancients for more answers. I really like it though. It would be great to have in any ancient collection.