Counterfeiting
Royal Mint survey results released in April 2012 found that an estimated 3.09% (just under 1 in 36) of all £1 coins in circulation are counterfeit. This rate has been increasing rapidly from 2.06% in 2008, to 2.58% in 2009, to 2.81% in 2010, and to 2.94% in 2011. In 2009, the highest levels of counterfeits were in Northern Ireland (3.6%) and the South East and London (2.97%), with the lowest being in Northwest England. Some estimates have placed the figure closer to 5%. An earlier survey in 2006 gave an estimate of 1.7%, which itself was nearly twice earlier estimates.
In July 2010, following speculation that the Royal Mint would have to consider replacing current £1 coins with a new design because of the fakes, bookmakers Paddy Power offered odds of 6/4 (bet £4 to win £10) that the £1 coin would be removed from circulation.
One common method of detecting counterfeits (if the sound of the coin on a table or the colour of the metal does not indicate something suspicious) is to check whether the reverse matches the edge inscription for the alleged year – it is extremely common for counterfeiters to get this wrong. Also, the writing on the edge may be in the wrong font and look very poor, and the coins often generally look much less sharply defined, lacking intricate details. Most counterfeit £1 coins in circulation are made of brass, and most lead copies are easy to spot and are quickly removed from circulation.
The Swazi lilangeni is minted from the same planchets as the British pound coin, and hence has the same chemical constitution, diameter, and mass. The lilangeni, however, is worth significantly less: the 2008 exchange rate is around 14 emalangeni to the pound. This has enabled it to be used for vending machine fraud, and payment fraud in situations where the receiver is unlikely to examine the coins closely.
Read more about this topic: One Pound (British Coin)