A very rare shilling of the Olkusz mint.
Issued during the short, barely two-month period of Piotr Zborowski's management of the mint.
He began placing his Jastrzębiec coat of arms only after the death of Jakub Rokossowski on July 13, 1580. However, this issuance was interrupted just two months later, on September 13, by the sudden death of the administrator.