On that coin site I found this link concerning counterfeit £1 coins. I wouldn’t think that it would be worth the price to counterfeit a £1 coin but this older article from the Independent gives some details:
According to coin industry sources, the economics of producing counterfeit coins, as opposed to notes, make it necessary to produce large amounts to net any kind of decent profit. Technically, it is relatively simple to produce fakes using dies made from the real thing; some are made from hand moulds, some on machines. All that is needed is sufficient nickel and brass. The kind of people doing this, in their backrooms and workshops, are most likely to be traditional criminals and gangs – Charlie Kray, elder brother of the infamous twins, was long suspected by police in London of involvement in counterfeit coin rackets.
One coin expert told The Independent that he had heard that £100 worth of counterfeit coins were being sold on the black market for £80 and £1,000 for £800 and so forth. “I think they could cost around 50p to 75p to produce, so you have to produce an awful lot to make it worthwhile,” said the expert, who added: “Frankly, if I get any, I just pass them on in my change, its not worth doing anything else.”
The real problem as far as I can see is that since coins don’t leave circulation for decades a counterfeit stays a very long time. Plus if you turn it in, you’re out a pound. I would think it is just too much work for the government to worry about it but this a newer article shows how the problem has grown:
The number of fake pound coins in circulation has doubled in the past five years and one in every 50 is now counterfeit.
The newer article has tips on spotting the bad ones and a small film as well. Apparently the fakes are getting worse, likely due to an attempt to bring down the cost of producing them. If the quality keeps dropping then the problem might fix itself.
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