What is the standard to measure the rare books in the Palace Museum?

The criteria for measuring the rare books in the Palace Museum include academic materials, artistic expressions and historical relics. The purpose and main responsibilities of the special collection of the Palace Museum Library: The purpose of the special collection is appreciation. The library of the Palace Museum is the business department of the Palace Museum, which manages and studies books, cultural relics and documents. Its contents are mainly historical records, celestial calculations, epigraphy, calligraphy and painting, Buddhist scriptures and the collections of various ancient scholars. In addition to a large number of Chinese books, there are also a number of Manchu, Mongolian, Tibetan and palindrome books. The main responsibility is to perform the collection and preservation, collection, selection, classification and cataloging, reading and circulation, restoration and protection, research and development, digitization and other work of rare books, ordinary ancient books, books, cultural relics and documents in the Ming and Qing Dynasties.