The Economist on the current state of coinage in the UK:
As counterfeiters have got better at producing copies, the number of fakes has grown to one in 30 coins in circulation, the mint reckons. One manager thinks it might be closer to one in ten.
That's an insane number.
The new coin’s first lines of defence are its bimetallic composition (a gold-coloured nickel-brass outer ring and silver-coloured nickel-plated-alloy middle), its 12-sided edge, evoking the threepenny bit, and tiny lettering cut into the inside rim. It also boasts a hologram-like “latent image” that changes from a pound symbol to a “1” when the coin is tilted.
Whoa, part 1.
Then there is what the mint calls “covert” security: a layer embedded in the coin which is understood to respond to signals of different frequencies (the mint is understandably saying little about it).
Whoa, part 2.
Authenticity can be verified by scanners at banks and in vending machines. To take advantage of this new feature, Britain’s half a million or so vending machines are being refitted with electromagnetic-signature detectors. Supermarkets have been replacing coin slots in trolleys.
Counterfeiting is clearly a massive issue (as noted above) if they're going to all this trouble...Read more...