A rare jadeite double-square seal believed to have been an Imperial seal of the Jiaqing Emperor, taken from the Summer Palace during Britain’s second Opium War with China in 1860, and brought to Britain by Liverpool born medical missionary, William Lockhart, will be sold on May 12th in London at Bonhams. The seal which measures under an inch square, is estimated to sell for £40,000 to £60,000. It is being sold with William Lockhart’s fan which is printed with a map of China on one side and a map of Beijing on the other. The location of Lockhart’s hospital in Beijing is marked with an X. The seal inscription reads Jiaqing Chen Han ('Jiaqing Emperor's Literary and Artistic Work') and Ji Xia Yi Qing ('When does one have the leisure to delight the heart?'