With far in excess of 30 milion fake old £1 coins in circulation, a new 12 sided, 'bi-metal' and supposedly 'counterfeit-proof' version, similar to above, will be launched in March 2017.
Some of the best Internet resources to help determine real and fake UK coins follow.
This page from the Royal Mint, links through to dedicated pages for all UK coins in circulation, including 1pence, 2 pence, 5 pence, 10 pence, 20 pence, 50 pence, one pound, two pound and five pound coins. There is also a dedicated page for the new one pound coin.
The Royal Mint also presents this pdf download explaining different designs for one pound coins, to help you determine whether a coin is real or fake.
See also Change Checker: for when your cash coins are more than just money.
