What makes a coin valuable? The 50 pence piece has become the most valued and collected coin in the UK, with many collectable designs appearing on its heptagonal canvas.

Its 27.5mm diameter makes it the largest of any British coin, and allows space for decorative pictures. It has often been used to celebrate big events over the past 50 years of British history.

The 50p Royal Mint coin, which was released to mark the anniversary of the American moon landings, is not in general circulation and is therefore highly sought-after by collectors.

Official figures for the mintage (number of coins produced) have not been released by the Royal Mint, but because the coin was never released to the general population, it is likely to be one of the rarest 50p coins on the market.

The uncirculated coin was recently purchased from a seller in Malvern for an eye-watering £29.99.

The buyer also paid an extra £2.25 for second-class postage.

The 50p is almost certainly rarer than the coveted Kew Gardens 50p, which has a mintage figure of only 200,000.

The Apollo 11 coin was released in 2019 and could only be scooped up through the Royal Mint's website.

It was never intended to enter general circulation, so if you're lucky enough to find this coin, you might want to consider buying a lottery ticket.

The coins are still legal tender and can be spent on goods, but very few will ever enter circulation as they have skyrocketed in price since they were released.

What makes a coin valuable?

The 50 pence piece has become the most valued and collected coin in the U.K., with many collectible designs appearing on its heptagonal canvas.

Its 27.5mm diameter makes it the largest of any British coin, and it allows space for decorative pictures. It has often been used to celebrate big events over the past 50 years of British history.

The rarest coins tend to be of the greatest value, with the mintage (number of coins with each design made) being the fundamental attraction for collectors.

Along with the design, other aspects of the coin which increase value are the condition of the coin and whether it has an error in its design.

The way in which it is sold can also determine the coin’s value - while some coin collectors will bid vast amounts of money on eBay or at auction, others opt for more robust valuations by selling via a coin dealer.

Rarest 50p coins in circulation the U.K.?

The Royal Mint has revealed the most valuable 50p coins in its collection.

The rarest is the Kew’s Garden 50p, which was designed to mark the 250th anniversary of the gardens in 2009. Only 210,000 coins were ever minted with this design.

The Kew Gardens 50p sells for £156.25 on average, but one seller received over £700 for one when they sold it on eBay.

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The other rarest coins stem predominantly from the 2011 Olympics, with the wrestling, football and judo coins among the most valuable. Only 1.1 million of each of these coins were produced.

Flopsy bunny and Peter Rabbit designs which were produced in 2018 are also highly valuable.

These coins - 1.4 million of which were minted - depict the characters from Beatrix Potter’s novels and celebrate the life of the English writer and these sell for around £5.

In 2019, 500 million coins were produced, with three new 50p designs.

These included one of Arthur Conan Doyle’s Sherlock Holmes, Paddington Bear at St Paul's Cathedral and the Tower of London.