A nice piece.
Well-preserved details.
Obverse: in the pearl rim a royal bust in crown, armor and cloak, with the Order of the Golden Fleece, to the right, under the bust initials I-T of Jan Thamm, minter of Cracow in 1656-57, in the outer rim the legend:
IOAN-CASIM:-DG-REX-P & S;
Reverse: in the pearl rim crowned with a four-cornered crown with 7 jewels in an open rim, with 5 fleurons, a five-field escutcheon with the coats of arms of the Crown, the Grand Duchy of Lithuania and the Snopes coat of arms of the Vasa dynasty, on the sides of the shield the denomination marking I-8, in the outer rim a legend punctuated by the coat of arms of Wieniawa Podskarbie Wielkiego Koronnego Bogusław Leszczyński superimposed on the shield and the initials I-C of Jakub Czamer, administrator of the mint in 1656:
COINS ARGEN-REGNI-PO:1656;