A nice piece of a rare and valued typological coin. Scratches on the surface, but at the same time the surface is healthy and glossy.
A distinctive issue both in terms of appearance and iconography. "Small" sixpence, as their diameter is ~21mm (rather than ~25mm like the standard John Casimir sixpences), the reverse of which is decorated with a crowned eagle, instead of a coat of arms shield. The obverse, in turn, features the Wieniawa coat of arms directly below the bust dividing the legend.
The only vintage issue of this denomination at the Wschowa mint for this king.