Experts study the Warring States Period's bamboo slips at Tsinghua University on Wednesday, October 22, 2008. [Photo: the Beijing Times]

Tsinghua University announced Wednesday that it is researching a collection of 2,100 ancient inscribed bamboo slips which date back to China's Warring States Period some 2,300 years ago.

The rare collection, which was donated to the university this July by one of its alumni from overseas who got them from an auction, is believed to be the biggest and oldest batch of bamboo slips ever found, the Beijing Times reports.

Inscribed bamboo slips were China's earliest form of "books" that carried valuable history records or classics of ancient periods.

Primary studies of these bamboo slips have found that they contain valuable material that was, until now, considered lost along with the classic book, "The Shangshu", or "The Book of History". They also contain other classics and some previously unpublished historical facts.

Another discovery was that the collection also includes some shortest slips that are considered the earliest "pocket books". They are less than 10 centimeters in length. The rest of the slips include some longest 46 centimeter ones.

A professor from Tsinghua's research team said that a special lab has been set up where experts from home and abroad were invited to help protect and research them. The first stage of the protection work has already been completed.

The group is now considering building a museum in which the precious collection can be put on display in the future.