Whereas some parts of the special collections are defined by their contents, such as the 90 dance of Death books and the 600 volumes with valuable handwritten annotations of their former owners, two further parts of the special collections differ from the rest in their printing technique. The 230 books printed in the copperplate engraving technique primarily mirror well-to-do life in the 17th and 18th century. The collection of lithographic prints focuses on the incunabula of lithography from the first 25 years (1796 to 1821) after the invention of the technique by Senefelder. The most famous vellum print is the prayer book of Emperor Maximilian I with margin drawings by Duerer and Cranach.