The Treasury believes there are almost 50 million fakes in circulation

The government is introducing new £1 coin in 2017 to counter the problem

Nine million fake £1 coins have been detected and withdrawn in five years

The Treasury has admitted they believe there are almost 50 million fake £1 coins in the nation's pockets.

Experts now believe that almost one in every thirty pound coins is a fake with around half of these counterfeit coins good enough to fool vending machine and automated tills.

In the last five years a total of nine million £1 coins have been detected and withdrawn by the Treasury.

The Tresuary has admitted they believe there are almost 50 million fake £1 coins in the nation's pockets

However, the number of fake coins being spotted has dropped in the last year as the forgers have got better at producing realistic-looking replicas.

Industry specialists say it costs around 20p per coin to make a fake £1 coin. The fakes are sold on the black market to distributors for around 70p each.

The problem has become so bad in recent years that the Government has announced it is to introduce a replacement for the £1 coin which will be harder to forge. These are due to come into circulation in 2017.

It has been designed by the Royal Mint and will be made of two different metals - like the £2 coin - and will be 12-sided.

A Treasury spokesperson said: 'These attributes together would make it the most secure circulating coin in the world.

A new £1 coin is due to be brought into circulation in 2017- and the Treasury believe it will be 'the most secure circulating coin in the world'

'One of the government's key economic objectives is to maintain confidence in the currency, and by introducing a new £1 coin with state of the art security features, the Government aims to safeguard the integrity of the coinage for the future.'

It is estimated that it will cost industry a total of £100million to update all the automatic tills, parking meters and vending machines to cope with the new coins.

While a genuine pound coin is made from a copper, zinc and nickel alloy, fakes are often produced using various metals to mimic the colour and composition.

TIPS ON HOW TO SPOT A FAKE It may not always be easy to spot a counterfeit £1 coin without close inspection. The Royal Mint has produced this guide on how to spot a fake: The date and design on the reverse do not match (the reverse design is changed each year) The lettering or inscription on the edge of the coin does not correspond to the right year The milled edge is poorly defined and the lettering is uneven in depth, spacing or is poorly formed The obverse and reverse designs are not as sharp or well defined Where the coin should have been in circulation for some time, the colouring appears more shiny and golden and the coin shows no sign of age The colour of the coin does not match genuine coins The orientation of the obverse and reverse designs is not in line Advertisement

Last year Dutch authorities said they had exposed an international smuggling ring which had shipped at least £30 million worth of fake coins to this country through sea ports.

A year earlier, three British men were jailed for a total of 12 years after a 40ft shipping container filled with 1.6 million blank coins, along with £85,000 of good to go' coins in buckets were seized in a van after a police operation spanning three counties. Another 30,000 coins were discovered concealed in the fake floor of one of the gang's cars.

In 2009 a plot to bring 500,000 fake pound coins to Britain from Italy was foiled by Italian police.

Fake £1 coins have become harder to detect over the years as forgeries have improved.

They can sometimes be spotted if the ribbed edge is poorly defined, or if the Queen’s head is indistinct. Sometimes the colour and weight can be slightly different.

Another sign of a dud is a misalignment of the ‘head’ and ‘tail’. If a coin is held with the Queen’s head upright, when turned around, the tail’s pattern should also be upright. If it’s at an angle, the coin is fake.

Since the introduction of the pound coin in 1983, the design on the other side from the Queen has changed every year in an attempt to stop fraud: this allows experts to compare the design with the year on the coin to see if they match.

Last year also saw the Bank of England recover a total of £11.7million in counterfeit bank notes.