’Jewels’ is a word which defines extremely valuable and unique items. Both categories may refer to insignia of power, signs of office, valuables of sentimental importance and ceremonial costume decorations. The exhibition at the Royal Castle represents a unique opportunity to see miniatures of the masterpieces from the private treasuries of Bona Sforza and Zygmunt August which have been brought in from Munich, Bern, Milan and New York.