Second vintage of trojaks with a royal bust in armor - one of the most distinctive depictions in Polish minting, which due to its uniqueness resulted in the colloquial calling of these issues (trojak and thaler) armorials.
A nice piece, well readable.
Obverse: bust of the king in a breastplate superimposed on a robe, with the Order of the White Eagle on an order chain of 7 links, in the rim the legend:
STANISLAUS AUG-D:G:REX POL-M:D:L-;
Reverse: crowned five-field escutcheon with the coats of arms of the Crown, Grand Duchy of Lithuania and Ciołek of the Poniatowskis, the escutcheon set on a laurel wreath with 3 berries in each branch, below initial g, surrounded by legend:
GROSSVS POLON:TRIPLEX-1766-;