With a thickness of 3.15mm, the coin was designed to be easy to make out from other loose change, although this has not stopped it from being targeted by counterfeiters - and almost three in every 100 pound coins are thought to be duds.
Ways to spot a fake include looking at how even the lettering is, seeing if the milled edge of the coin is even and well-defined and examining the colour. Genuine £1 coins which have been in circulation for some time appear more shiny and golden.
More information about how to spot a fake £1 coin is on the Royal Mint's website here.
More top news
Rain clearing east tonight for a dry but fresher day tomorrow with plenty of sunny spells.
Heavy rain clearing east for a dry but fresher day tomorrow with some hazy sunshine.
Rain becoming heavy at times this afternoon before clearing tonight. Dry with hazy sunshine tomorrow but feeling fresher.