Check your change immediately as you could have a fortune sitting in your pocket. Whether it's a rare 20p coin with a problem, or the rare 50p coin with 200,000 in circulation – certain bits of change are worth keeping an extra eye on.

Now if there's plenty of rare coins in your stash, you might have stumbled on this special one penny. Instagram user @CoinCollectingWizard has a huge following of 30,100 fans on his platform where he shares the hidden gems which you need to look out for. He recently discussed the "British penny that could change your life overnight" – so do you own it?

In the post, he wrote: "Imagine finding a humble old penny in your change... only to discover it's worth a fortune.

"That's exactly the case with the legendary 1933 British penny – one of the rarest coins in UK history."

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According to the collector, only six genuine example are known to exist and none of these would have been released for general circulation but more struck for ceremonial reasons.

"If you somehow stumbled across one, you could be looking at hundreds of thousands of pounds at auction," he added.

"The catch? Because they're so famous, there are far more fakes than real ones."

He continued: "Many replicas were made over the years, so before you start planning your dream holiday, always get your coin verified by a professional.

"The 1933 penny is the crown jewel of British coin collecting – but sadly, finding one in your change is like winning the lottery... twice."

This special coin is known as the 1933 George V penny which experts believe has an estimated value of £72,000.

The reason it's incredibly rare to find one of these in your stash is because these weren't intended for circulation, so therefore have never been issued to the public.

Some of these are "uniface", that is they are single-sided, the opposite side remaining blank.

So how do you know if your coins are rare?

Firstly, it's worth checking the year as this will tell you a lot about the penny's value.

Secondly, make sure you look for errors, double ties, wrong metal use or even the incorrect date as these can significantly increase a coin's value.

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