A rare book refers to a book with complete content, rigorous collation, exquisite engraving and no text errors, and the book must be old enough or rare enough. Old refers to being close to or even the original. So it is also very precious, but if there is more than one book, it can't be called an orphan.
Attach a complete and detailed description of rare books by the state:
(1) Books carved or copied in Yuan Dynasty and before.
(2) Books engraved and copied in the Ming Dynasty (except those whose versions are vague and widely circulated).
(3) Printed copies and manuscripts rarely circulated before the Qianlong period in the Qing Dynasty.
(4) Books published by the Taiping Heavenly Kingdom and the peasant revolutionary regimes of past dynasties.
(5) Before the Revolution of 1911, there were manuscripts with original opinions or school characteristics in academic research, or with systematic opinions, as well as rare printed editions and manuscripts.
(6) Manuscripts, rare editions and manuscripts reflecting a certain period, a certain field or an event before the Revolution of 1911.
(7) Before the Revolution of 1911, famous scholars proofread, engraved or copied the printed matter and manuscripts that had been proofread by predecessors and had reference value.
(8) In printing, it can reflect the development of printing technology in China, representing various movable type books, overprint books or block printing with exquisite prints in a certain period.
(9) Printed plates of Ming Dynasty, ancient printed plates of Qing Dynasty and seal cutting by famous artists (with characteristics or handwriting).