The UK’s Royal Mint introduced its new 12-sided one pound coin on Wednesday, packed with features to prevent forgery – and immediately ran into problems with vending machines and supermarket trolleys, as well as a high demand for the new coin.

The UK's Royal Mint introduces its new 12-sided one pound coin on Wednesday.

The Royal Mint’s website crashed as thousands of people sought information on how to get hold of the new coin, which replaces the old, round pound coin introduced in 1988 to replace the old one-pound banknote.

A spokesman for the Royal Mint said: “We are experiencing quite a high demand at present from people interested in the new coin – both commemorative and circulating editions.”

Several supermarkets reported problems with people attempting to use the new coin for trolley rental – the supermarket Tesco said it had had to unlock its trolleys for free use as a result. Some supermarket trolleys, especially in the southeast of England, carry dual slots, and the new pound coin will fit the slot made for the euro coin.

Most vending machines have not yet been adapted for the new coin, which is heavier and larger than its predecessor.

The Royal Mint said the new coin, made of two metals – an outer rim of gold-coloured nickel brass, and the centre silver-coloured nickel-plated alloy – also includes a hologram image on the coin, micro-lettering on the side and a “hidden high-security feature” that the Royal Mint is not revealing.

The Royal Mint estimates that one in 30 of the old coins are fake, and shops will not accept them after October 15.

The new coin follows the introduction of the new polymer five-pound note introduced with much fanfare earlier this year.

Its plastic-like feel means it is waterproof and famously, in a publicity stuntstaged by the manufacture, can be dipped in curry without any ill effects.

One promotional gimmick to help the note gain acceptance was that four of the new notes, featuring the celebrated 18th-century author Jane Austen, contain a secret engraving which, if detected, meant the note’s owner won 50,000 pounds ($62,110). Two have been redeemed, with two still out there, according to The Sun newspaper.