A nicely preserved piece.
Interesting minting error in the form of the ghost of the royal head visible on the reverse.
Obverse: head to the right, in the rim legend:
STANISLAUS AUG.D.G.REX POL.M.D.L.;
Reverse: crowned five-field straight shield of arms with the coats of arms of the Crown, the Grand Duchy of Lithuania and the Ciołek coat of arms of the Poniatowskis. Lower initials E.B. and the denomination 4.GR., on the sides of the shield the date 17-90, in the rim the legend:
83 1/2 EX MARCH-PURA COLON:;