Among Chinese collectors of antiquities, power and patriotism sell, or at least that is the assumption Sotheby's is making as it prepares for the spring auction season next month.

A collection of rare objects owned by Qing dynasty emperors will fall under the hammer, including a white-jade seal carved for Emperor Qianlong that is expected to fetch more than US$6.5 million. Other imperial memorabilia for sale will include an 18th-century ceremonial pearl necklace and a ruyi scepter carved of boxwood, both believed to have been owned by Emperor Yongzheng.

The theme of the promotional materials, 'Imperial Power,' is designed to appeal to collectors from China keen to buy artwork and antiquities from their own country, said Nicolas Chow, Sotheby's senior director for China and Southeast Asia. Many are business people, often with 'a clear sense they are buying their history back,' he said.

For these buyers, an association with power and authority carries more clout than the usual approach taken with Western buyers of Asian collectibles. That approach is summed up by the title of a catalog for the same April 8 Hong Kong auction presented to Sotheby's European and North American clients: 'Objects of Contemplation.'

'It is really about pitching the right piece to the right clients and presenting the objects in such a way that our clients can make sense of them with their respective set of references,' said Mr. Chow. 'It is about understanding the objects, what they are, what they say, and having a solid grasp of our diverse clientele.'

Buyers from mainland China have become important to the major auction houses. As China's economy expanded, wealthier Chinese auction buyers were gaining ground on their Western counterparts. The global economic downturn, which was less severe in China, accelerated their rise.

That makes it more important for auction houses to tailor their marketing to the Chinese, who are active in other categories as well.

Bonhams, which opened a Hong Kong office in 2007, initially sold only art, but soon added watches, jewelry, wine and even whiskey to its roster of Hong Kong auctions. The company also plans more promotional events on the Chinese mainland.

A representative for Christie's International PLC said it promotes auctions by choosing 'the most appropriate lots from a sale to highlight in different countries,' including countries in Asia. 'The choice of such lots is made with careful consideration of cultural tastes and sensibilities,' the representative said.

Christie's ran into trouble with the Chinese government last year when it auctioned off two animal bronze heads looted from China's Summer Palace in 1860. Nevertheless, the company saw the value bought by Chinese buyers world-wide in its sales rise 94% in 2009 compared with the previous year.

In a sign of the importance of the Chinese market, Christie's has dispatched one of its most experienced staffers to head its Hong Kong-based Asian operations. Francois Curiel, who has been with the firm for more than three decades, previously was head of Christie's jewelry division and its European chief.