China-based auction house Guardian is getting warmed up for its autumn sale scheduled later this month. On Wednesday, Guardian brought out the three hundred lots for a preview in Shanghai.

The preview lots cover a wide spectrum, ranging from paintings, calligraphy, and porcelain, to ancient scripts and jewelry.

The leading lot is a piece of calligraphy from Wang Xizhi, China's most celebrated calligrapher who lived some 1600 years ago. The piece adheres to another calligraphy claimed to be done by Emperor Qianlong in the Qing Dynasty.

Hu Yanyan, Guardian Auction House, said, "It is obviously Qianlong's writing style, and the seal is also genuine. Based on these facts, we can be sure that this is a priceless piece of Wang Xizhi's calligraphy that must have been among Qianlong's own collection."

The piece was split into two parts. It's the first part, containing forty one characters, that will go under the hammer. The lot may be small in size, but it stands a good chance of fetching quite a large sum -- perhaps over one hundred million yuan.

A self-portrait by Zhang Daqian is among other top runners at the preview. It was executed in 1969 when Zhang turned 70, and was a gift to the artist's fourth wife.

The Shanghai preview ends on Friday, before Guardian opens its autumn sale on November 20th in Beijing.