An undescribed variety in the specialized catalog "Groszes of Głogów and Cracow of Sigismund I the Old".
Unlisted combination of stamps - obverse with a crown with four arches in cross-section and a very rare variant of the reverse - with punctuation in the form of arrows.
This variant was so far unknown to the author of the catalog, who rated its rarity at R*.
Very nice state of preservation.