The real value of that piece is not from the coin (which is pre-modern, early 1600s) but as an antique jewelry piece recovered from a shipwreck. The coin itself might have a value but because of the mounting (it seems to be soldered in) would be less than a coin which was not mounted.
Best to take it to an antique dealer/valuer or dealer in estate jewelry to get an estimate.
Best to take it to an antique dealer/valuer or dealer in estate jewelry to get an estimate.






















