A craft of Hotan jade. [Photo provided to China Daily]

Commenting on the book, Xu Lin, a researcher at the Palace Museum who specializes in jade ware, says: "From my perspective, the merit of this book is that it has listed different historical periods of jade mining, and presented almost all the historical records we can find today about Hotan jade," adding that Yu's book is a milestone in the complicated research on the particular jade.

But she has some reservations about his claim that it was Zhang Qian who discovered and introduced the jade to the central plains.

Responding to her doubts, Yu says he welcomes a discussion on his work.

Speaking of his motivation to write the book, the author, who has been obsessed with jade since 1974, says the history of jade is part of Chinese civilization.

"We must care more about the history and cultural value of jade rather than just its price. The stone, which is beautiful, should be cut and chiseled to continue serving as the carrier of Chinese civilization."