Today, March 28, the Royal Mint will release 300 million new £1 coins. The new coins are 12-sided, slightly thinner than old pound coins, and are bimetallic like the £2 coin. Perhaps most intriguingly, though, the Royal Mint says the new £1 coin is “impossible” to fake because of a top-secret security measure.
There are currently around 1.6 billion round pound coins in circulation in the UK, and the Royal Mint estimates that 2.55 percent of them—about 40 million pounds—are fake. Over the next few months a total of 1.5 billion of the new £1 coins will be released, and then the old coin will be officially retired on October 16 (you’ll still be able to bank any leftover round pounds, but shops and machines will stop accepting them). The old pound coin, in case you were wondering, has been in circulation since 1983.
The new coin has a number of features that make it both harder to counterfeit and more ergonomically friendly. To begin with, unlike any other coin in circulation in the UK, it has 12 sides, making it instantly recognisable as you fumble around in your pocket or purse. Further assisting the blind and visually impaired, the edges of the new coin alternate between smooth and milled.
On the obverse (heads) sign of the coin there’s the Queen’s head, and on the reverse (tails) side there’s a nice motif featuring the four vegetacular motifs of England, Wales, Scotland, and Northern Ireland. The reverse side design will be changed regularly, just like other coins.
Moving onto the various security features of the new £1 coin, around the rim of the coin is an inscription that’s crafted with an expensive, special laser that counterfeiters are unlikely to have access to. On the obverse (heads) side of the coin there’s a “latent image”—a small, hologram-like feature: from one angle it looks like the number 1, from another it looks like the pound sterling symbol £. The new coin’s bimetallic design (silver nickel-copper surrounded by gold nickel-brass) also makes it much harder to copy than the old pound coin.
Finally, there’s a hidden security feature, which the Royal Mint is being rather coy about. All we know is that you need a machine to detect it, and that it has been used on bank notes before. Gordon Summers, chief engraver at the Royal Mint, told Wired UK that the new security feature “is currently impossible for those counterfeiting coins to copy—it’s not difficult to do, it’s impossible.”
The most obvious answer is something like a tiny RFID/NFC chip that emits a cryptographic signature—but reading RFID through solid metal is tricky. If I had to guess, it’s probably a small layer of another metal or material deep within the coin—something that changes the electrical conductance or magnetic field of the coin when stimulated. Or maybe it’s an RFID chip that’s only under a very thin layer of metal.
You’ll start to receive new pound coins from banks, shops, and machines today. Both coins will be in circulation for about six months, followed by demonetisation of the old coin on October 16. If you want a shiny, uncirculated new pound coin you can buy one for £10 from the Royal Mint, or a special sterling silver version for £75. As always, there’s also some new pound coins in circulation with minting issues that are worth a lot to collectors: keep an eye out for coins that are dated 2016, or where the silver inner section is poorly aligned.
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