Yes, I believe you have a silver grosz from the Polish city of Danzig. It is listed in Krause as KM#11. The obverse shows King Sigismund III. The date is 162* (I can't read the last number). The value is probably going to be around $10.
hi thanks for the information, where is the date located and i cant find one with the exact same picture on back so could this be a rare one?