​The online listing on eBay, posted by a private seller from Bishop Auckland, advertises a 2017 Beatrix Potter “The Tale of Peter Rabbit” 50p coin with an asking price of £18,086.70, or best offer. The coin is part of the hugely popular Beatrix Potter collection, which has become one of the most sought-after series among UK coin collectors in recent years. While millions of Peter Rabbit-themed 50p coins were produced, certain versions, particularly those in pristine condition, limited releases or with specific features, can attract significant interest online. The high asking price follows growing attention around rare 50p coins, after a Blue Peter Olympic 50p recently sold for hundreds of pounds at auction, despite having a face value of just 50p. That coin, designed by a Blue Peter competition winner to mark the London 2012 Olympic Games, was never officially circulated, with only around 20,000 produced. Some have since changed hands for well over £200. Coin experts say a coin’s value is determined by a combination of factors, including mintage numbers, condition, demand and whether the coin contains any minting errors. Although online listings can feature eye-catching price tags, collectors are often advised to research recently sold prices, rather than asking prices, and to seek professional valuations where possible. The Royal Mint has previously said that while some coins can be valuable, many listings reflect sellers’ expectations rather than guaranteed market value. 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: Atlantic Salmon (2023), 200,000 Kew Gardens (2009), 210,000 Olympic Wrestling (2011), 1,129,500 Olympic Football (2011), 1,161,500 Olympic Judo (2011), 1,161,500 Olympic Triathlon (2011), 1,163,500 Peter Rabbit (2018), 1,400,000 Flopsy Bunny (2018), 1,400,000 Olympic Tennis (2011), 1,454,000 Olympic Goalball (2011), 1,615,500 Just because a coin is listed for £18,000, doesn