POLAND: 1/2 Thaler (4 Zlotych) (1768 IS) in silver (0,833). Head of King Augustus Stanislaus facing right on obverse. Crowned, round 4-fold coat of arms within sprigs on reverse. Inside slab by NGC "AU 55 / M.D.L.". Unique in pop in both companies. Cert number: 6636960-003. (KM 191.1). Ex Dr Ntzelepis collection. Rare!