Steve Hurst requested a full ID and a valuation on this hammered silver coin, which is 25mm in diameter.
This find is a sixpence of Elizabeth I. It is dated 1584 above the shield on the reverse but I can’t be sure of the mint mark as it is smudged on both sides. However, it will be a scallop or (most likely) a letter A.
The obverse is only Far but the reverse is slightly better so my price range would be £25 to £30.