First, very rare vintage half-penny of Sigismund II Augustus.
Variety with the king's titular inscription on the eagle page.
Undescribed in the catalog of the Ivanauskas-Cesnulis duo hybrid of stamps: with DVCAT9 (instead of the popular DVCATVS) and L / LITV endings.
Nice, only slightly bent.
Piece from the collection of Tadeusz Kalkowski, complete with his envelope.