

The first cash machines used Carbon-14 to check authenticity - jgrahamc
http://news.bbc.co.uk/1/hi/6230194.stm

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jgrahamc
If you have access to the IEEE Annals of History of Computing then there's an
interesting article that delves into the history of the cash machine in the
UK.

[http://www.computer.org/csdl/mags/an/2011/03/man2011030032-a...](http://www.computer.org/csdl/mags/an/2011/03/man2011030032-abs.html)

Prior to the invention of the plastic card this system used paper cheques
impregnated with carbon 14 and an associated PIN to 'cash' the cheque and turn
it into cash at a machine.

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tocomment
Actually this gives me an idea. Could you use carbon dating to compare a bills
age with the serial number or date minted to prevent counterfiets?

Or perhaps the treasury could start embedding carbon 14 into bills?

(wow I really need to start patentng this stuff!)

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arethuza
Euro notes already have small amounts of the element Europium within them as
an anti-forgery mechanism - which might be prior art :-)

<http://en.wikipedia.org/wiki/Europium>

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tocomment
I wonder how they chose that element...

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__alexs
Interestingly he even appears to have predicted Google Wallet.

"He believes fervently that we will soon be swiping our mobile phones at till
points, even for small transactions. "

