A POSTMISTRESS has been left stunned after a botched £1 coin turned out to be worth more than 600 times its face value.
Diane Bath, 62, who runs The Post Office in Broughton-in-Furness, Cumbria, said took a delivery of new change stamped with King Charles’ face.
But “hawk eye” staff spotted that a £1 coin in the delivery appeared to be entirely gold.
The error by The Royal Mint - said to be incredibly rare - meant that it was all brass, rather than the two-tone nickel.
So far, it’s believed to be one-of-a-kind and experts say it could fetch hundreds at auction.
Diane, who has been a postmistress for over 20 years, said: “I am absolutely over the moon.
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"Obviously we handle cash all of the time and it’s the most exciting find I’ve ever had in over two decades.
"I had a look online and couldn’t see one like it, so I knew it must be worth a decent amount.”
Diane contacted some experts and was told it could be worth around £600, but Oliver Reece, British Coin Specialist at Baldwin’s, said it could fetch more at auction.
He said: “It may not be unique but certainly they are, by their very nature, rare things and the market is quite strong for modern errors.
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"I should think it would be worth a good few hundred pounds but you never know how these things will go at auction as there are often no direct comparisons.”
Diane said she’s keen to sell it at auction, after getting it verified, in case “more come into circulation”.
She added: “At the minute I think it’s one-of-a-kind so I would be interested in trying to sell it."
A The Royal Mint spokeswoman said: “The Royal Mint has tight quality controls in place and the chance of encountering any UK coin with error is exceptionally low.
“We always urge collectors to be cautious and to do their research.”
Last month, it was revealed that a batch of ultra-rare Aquatic 50p coins made with a misprint are worth thousands.
Only 600 with an error were manufactured in 2011 ahead of the London Olympic games.
They’ve had collectors battling it out, with one going for a whopping £3,766.
In August it was said that a £2 coin released in 2014 to mark 100 years since the First World War could be worth thousands.
There are only a few in circulation with the misprint which fails to include the words £2 from the head side.
Last year, Rachel Hanson, 38, picked up a rare £1 coin which had been stamped twice while buying her Chinese takeaway.
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The full-time mum-of-two from Melksham, Wiltshire later flogged it for £250 to help pay for her energy bills.
A 2009 Kew Gardens 50p printed in error is also a “rare find”, fetching for over £140 at auction.
How can I check if my error coin is genuine?
RARE and valuable coins can go for a hefty sum - but how do you know if your coin is the result of a genuine minting error?
The best way to find out if you have an error coin is to send it to the Royal Mint museum, which will analyse it and see if it is a result of a genuine minting error or not.
It'll normally take a couple of weeks to get the results back to you.
But remember, there's a difference between a genuine error coin and one that is just imperfect, for example with a design that is not as clear as you'd expect.
And whatever you do, don't be tempted to splash your cash without evidence from the Mint confirming that it's a genuine error.