How does a 20p become worth £50...
How great would it be if you had a twenty pence peice in your purse or pocket and it turned out it was worth £50...
Well you could have if you live in the UK.
The Royal Mint, who creates the coins made a mistake when they made their first batch of new 20p peices.
They forgot to put the date on them, so if you have one of the coins you could sell it for £50, the expected new value of what these 'wrong' coins are worth.
The old 20p used to have the date on the tails side of the coin, but when the Royal Mint designed new coins they removed the date so it was always now on the heads side of the coins. The queen's head side on the rest of the coins didn't require updating.
But when they started to mint the new 20p they used the old updated Queen's head side without the DATE as they forgot the 20p heads side didn't have a date.
So there you have it, a coin with no date.
Nick Hart, from the London Mint Office said "We believe this extremely rare error will certainly get the public looking at the coins in their pockets again and noticing the excellent new designs launched by the Royal Mint on our coinage."
"Mistakes like this not only fascinate people but also have considerable value-increase significance."
I'll be checking my pocket every day...
What to look for
The special coins will have the new design on the back, but the old design on the front.
This means there will be no year on them anywhere. If you have one of the newly-designed 20p coins, check the front side with the Queen's head on it: if there is no date there, you might have found a coin worth £50.
How did this happen?
Last year the Royal Mint re-designed seven of the UK's coins. In most cases all that was needed was a new design for the back, but in the case of the 20p piece a new design was needed for the front as well.
That is because, traditionally, the date on 20ps was placed on the back of the coin, whereas with the new design it had to fit on the front with the Queen's head.
Someone at the Royal Mint forgot to make this change and a series of coins were struck with the old head (without a date) and the new tail (also without a date).
How to cash in
And what should you do if you find one of these special 20ps in your pocket, wallet purse or change jar?
A service has been set up to buy them from you. The London Mint Office, a private company not connected to the Royal Mint, is offering £50 to anyone who has one of the 'faulty' 20p coins. You must register online to be eligible: http://www.undated20p.com/