Do not always take the small change in your pocket at its face value - it could be worth a lot more than you think.

The Royal Mint has given people a run for their money with a number of treasury mistakes that have resulted in the production of rare coins and interesting stories to go with them.

So while you might dismiss the shrapnel in your pocket as parking change, perhaps you should be taking a closer look at what it could be worth.

The Dateless 20p

Regarded as the Holy Grail of coin collecting, the 20p saga of 2008 encouraged an entire country to start carefully checking their change. That year, an error at the Royal Mint produced hundreds of thousands of 20p coins that do not have 2008 stamped on them.

The blunder occurred after a redesign of the 20p coin, where the old heads side was used with the new tails design. The Royal Mint does not know exactly how many of the "dateless" coins were produced and released into circulation, but estimates about 250,000 of the 136 million pieces minted.

This is the first undated British coin to enter circulation in more than 300 years and they are worth up to £50 each on auction sites.

The Kew Gardens 50p

But if you think finding a dateless 20p is lucky, those who have found the coveted Kew Gardens 50p are much more so.

You are twice as likely to find an undated 20p as you are a Kew Gardens 50p, which were released in 2011 to celebrate the 250th anniversary of the Royal Botanical Gardens.

The Royal Mint released just 210,000 of these coins, making it the rarest in circulation. The 2012 London Olympics Coin

To celebrate the 2012 London Olympics, The Royal Mint released a 50p coin with 29 different designs, some of which were produced more than others.

A full set of coins can fetch around £35 at auction, with a lone football, wheelchair rugby, wrestling and tennis piece being worth £3 to 4 each.

One design on these Olympic 50p coins though is worth gold - the original aquatic design, which depicts a swimmer with water passing over their face, is worth £3,000 on eBay.

Only 600 of these coins were minted before the design changed slightly to make the swimmer's face visible.

The New Pence

Until 1981, all 2p coins had the words "New Pence" inscribed on the tails side, but a year later The Royal Mint decided to change it to read "Two Pence".

Then, in 1983, the Mint accidentally circulated a small number of coins that bore the original "New Pence" inscription on them. Many of these have been snatched up by collectors, but if you can find one in your piggy bank it could be worth up to £650.

The Silver 2p

In June, another type of ill-struck 2p was sold at auction for £1,350.

This is down to a change in the material it is made from - instead of copper-plated steel, this rare coin is made from the nickel-plated steel used for 10p coins.

The error was discovered by Royal British Legion volunteers in Wiltshire who thought the coin was a fake when they discovered it in a Poppy Appeal tin last year. When they took it to a bank, The Royal Mint confirmed it was the real deal.

A similar nickel-plated steel 2p was sold at auction for £1,357 in 2014 and another fetched £802 in an eBay auction last year.

To read the complete article, see:
The Kew Gardens 50p and other rare coins that could turn your small change into a fortune (www.hulldailymail.co.uk/the-kew-gardens-50p-and-other-rare-coins-that-could-turn-your-small-change-into-a-fortune/story-29647221-detail/story.html)