A retired chocolate factory worker who took an old vase to a provincial auction house in a cardboard box is in line for a million-pound bonanza after being told it was a Ming moonflask.
Experts at Duke's in Dorchester, Dorset, were stunned when the 79-year-old man, who used to work for Cadbury, showed them the 29cm-tall vase, thought to date from between 1403 and 1424.
The vase was made during the reign of Yongle – the third emperor of the Ming period – features simple loop handles and appears to be influenced by Islamic design.
Guy Schwinge, from Duke's, said he was stunned when he first saw the elegant blue and white piece.
"When my colleague initially showed me what had arrived in a cardboard box I could not believe my eyes," he said.
"The vase is in perfect condition and it is amazing to think that it has survived unscathed for almost six hundred years.
"It is the largest recorded example from a rarefied group of early Ming moonflasks dating from the Yongle period."
Giuseppe Eskenazi, a London-based Chinese art dealer, who has seen the vase, said: "It is very fine and should do very well. It is very rare and in 50 years I have only seen three flasks like this."
Anthony du Boulay, Duke's consultant for Chinese works of art, described the vase as "a spectacular find", adding: "It is a rare survival, which will undoubtedly appeal to mainland Chinese collectors and institutions. What makes this vase interesting is its size compared with the other known Yongle vases of this type."
Last year, Duke's sold a Chinese vase from the Qianlong period for £765,000. It had been used as an umbrella stand by its owners.
It is not known for how long the 79-year-old man had the vase or what he paid for it.
The sale is on 12 May. Because of its Islamic influence, potential buyers are likely to come from the Gulf states as well as China.