Image copyright AFP/Getty Images Image caption The seal features nine dragons which signify masculinity and the imperial authority

An 18th Century Chinese imperial seal has been sold for a record €21m (£18m, $22m) - more than 20 times its estimated price.

The sale, to an unnamed Chinese collector, took place in Paris on Wednesday after a heated bidding war, Drouot auction house said.

The palm-sized seal is made of red and white steatite, a type of mineral rock.

It was one of hundreds owned by Emperor Qianlong, one of the longest serving Chinese emperors.

The previous record set for an auctioned seal was €14m in 2011.

Intricate craftsmanship

The latest seal sold was originally acquired by a young French naval doctor who visited China in the late 19th Century, and had remained in his family ever since, Drouot said (link in French).

Asian art expert Alice Jossaume told AFP news agency it had been expected to sell for between €800,000 and €1m.

Emperor Qianlong, an avid art collector who ruled China for much of the 18th Century, was an artist himself who would use seals to sign his works, and commissioned some for their intricate craftsmanship.

The seal sold on Wednesday features nine dragons which signify masculinity and the imperial authority.

Drouot said more than 1,800 Qianlong seals were made, out of which 700 disappeared. Another 1,000 are kept by China's Palace Museum in Beijing's Forbidden City.