A copy of the Royal Mint's rarest coin in circulation has sold for nearly 400 times its face value on eBay this week.

The King Charles III Atlantic Salmon 50p sparked a mini bidding war amid coin collectors on the auction site, as 22 bids were made on the rare coin before it sold for £195.

The Royal Mint recently named the coin as the rarest currently in circulation in the UK, with just 200,000 copies minted.

The coin knocked the “highly collectable” 2009 Kew Gardens 50p off the top spot for the first time in 15 years, the official maker of British coins said.

(Image: Royal Mint/PA Wire)

Last year marked the final chapter of Charles’ transition onto UK coins, with coins commemorating the coronation and new designs across all denominations from the 1p to £2.

Each design highlights Charles’ “passion for conservation and the natural world”, featuring wildlife such as the hazel dormouse and bees, the Royal Mint said.

Described by the Royal Mint as “the nation’s most collectable coin”, the 50p has seen over 100 different designs appear on its reverse since its introduction.

Out of the 10 rarest 50ps in circulation, six are related to the 2012 London Olympic and Paralympic Games, with Peter Rabbit and Flopsy Bunny coins from 2018 both also making the list.

Five Incredibly Rare and Valuable British Coins

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 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.

Royal Mint top 10 most valuable 50p coins

Here is a list of the top 10 most valuable coins, when they were made and how many were minted:

  1. Atlantic Salmon (2023), 200,000
  2. Kew Gardens (2009), 210,000
  3. Olympic Wrestling (2011), 1,129,500
  4. Olympic Football (2011), 1,161,500
  5. Olympic Judo (2011), 1,161,500
  6. Olympic Triathlon (2011), 1,163,500
  7. Peter Rabbit (2018), 1,400,000
  8. Flopsy Bunny (2018), 1,400,000
  9. Olympic Tennis (2011), 1,454,000
  10. Olympic Goalball (2011), 1,615,500