A rare 20p coin made with a glaring error in its design has sold on eBay for £57.
It is understood that hundreds of thousands of these so-called "mule" coins were released into circulation in 2008 after a mistake meant that the date was not minted on them.
It came as the Royal Mint was altering the design of the 20p piece to move the year from the back to the front of the coin, next to the silhouette of the Queen, reports the Mirror.
But, in some cases, the old die was accidentally used, leaving a batch without a date on either side.
Experts at Change Checker believe that no more than 250,000 mule coins made it into circulation.
As these were the first undated coins in use in the UK for more than 300 years, they have become particularly valuable to collectors.
The coin that sold on eBay, for example, attracted 13 bids from seven people before settling on the price of £57.
So, keep an eye out for error coins in your change as they could be worth a pretty penny.
If you're thinking of buying one at an auction, be aware that some fakes are also in circulation.
You can get coins verified by the Royal Mint to check they're the real deal.
