This Chinese vase sold for more than $1 million. Picture: Fellows/PA

One lucky seller has become an accidental millionaire after the Chinese vase they wanted to auction sold for 450 times its valuation.

Auctioneers at Fellow and Son were left scratching their heads after the piece, originally thought a copy, turned out to be a 500-year-old antique. It was made during the reign of Emperor Jiajing of the Ming dynasty, who ruled from 1521 to 1567.

Eagle-eyed buyers recognised the value of the antique and ignored the house's valuation of $A2913. One eager collector even flew in from Japan to secure the treasured item.

To say the bidding was fierce is an understatement. It started at a mere $A1619. In the end the porcelain wacai fish vase sold for $1.31 million. The incredible sale broke records for the Birmingham auction house in the UK.

Fellows senior specialist, Mark Huddleston told the Telegraph UK: “Two buyers in the room battled each other strongly before, at around the £600,000 ($A971,000) mark, the final telephone left standing sparked into life. There was a lot of interest through the online bidding platforms as well.”

“Finally at £800,000 the final bidder in the room admitted defeat, and with the next bid the telephone bidder, via his translator, secured the lot — to a round of applause for the auctioneer and Managing Director, Stephen Whittaker.”

Mr Huddleston added, “We are delighted with the house-record sale of the Chinese wucai vase. This vase was consigned via a Chinese client.

“Initial research when cataloguing had pointed to a number of historic precedents sold in the tens and hundreds of thousands.

“We examined the decoration to the collar and felt that it lacked sophistication of these early pieces.

“While we dealt with a number of condition inquiries before the sale, little could have prepared us for the result.”

And with a simple case of mistaken identity, the lucky seller is laughing their way to the bank.