This fine miniature stone mosaic is probably identical with the one recorded in the inventory of the estate of Karel Škréta the younger, dated 1691. It represents the family coat-of-arms assigned by Emperor Maximilian II to Johann Škréta, grand - father of the painter Karel Škréta the elder and councillor of the Old Town of Prague. A heraldic monument of this type is unique in the milieu of the Prague knighted burghers. From the Rudolfine era, the costly and elaborate arts-and-crafts technique pietre dure found its clients especially at the court and among the high aristocracy and clerical orders. This object testifies to Karel Škréta’s high professional confidence, and perhaps also to the painter’s friendly relations to the court gem-cutter Dionysius Miseroni, who from 1634 was also employed as the manager of the imperial Kunstkammer at Prague Castle. The other side of this friendship can be proved by the famous group portrait of Miseroni and his family by Škréta.