10 years ago: counterfeit coins


© Shutterstock

Recently I discovered a £1 coin which was slightly more golden than others, and a more detailed examination showed a minting date of 1990 and a Scottish reverse. A report of these facts to the Royal Mint confirmed that this was a counterfeit coin. Despite the above information, and certain other minute details, this was clearly a match for a true £1 coin and had escaped the attention of previous recipients. Having sent the coin to the Mint, I have now been informed that x-ray fluorescence (XRF) spectrometry showed it to be made of leaded brass rather than the usual alloy.

Letter from J D R Thomas in Chemistry World (February 2004)

 

Ed. Recent surveys have shown that as many as 3% of all UK £1 coins are indeed counterfeit, though the number has fallen slightly in the last year or so.As a result, there have been several calls for the Royal Mint to scrap the entire denomination and reissue it. Genuine £1 coins consist of an alloy of approximately 70% copper, 5.5% nickel and 24.5% zinc. XRF analysis remains the favoured technique for the analysis of coins both ancient and modern.


Related Content

Coin isotopes unravel ancient inflation riddle

24 May 2011 News Archive

news image

Isotope analysis of silver coins sheds important light on economic inflation in Europe in the 16th and 17th centuries

Chemistry World podcast - December 2013

3 December 2013 Podcast | Monthly

news image

We discover how spin chemistry guides migrating birds and explore the science of cheese

Most Read

Antimicrobial resistance will kill 300 million by 2050 without action

16 December 2014 News and Analysis

news image

UK report says resistance will cost global economy $100 trillion

Cutting edge chemistry in 2014

10 December 2014 Research

news image

We take a look back at the year's most interesting chemical science stories

Most Commented

Smart skin for prosthetic limbs senses heat and touch

12 December 2014 Research

news image

Ultra-thin plastic skin can bend and flex without affecting the skin's ability to detect stimuli

Chemistry behind the ‘blue man’ unlocked

1 November 2012 Research

news image

Biochemical model suggests that silver ions, not nanoparticles, cause a rare skin complaint