The world’s rarest stamp is returning to Britain permanently for the first time in 143 years. The British Guiana 1c Magenta (1856), which has been described as “the Mona Lisa of the stamp world”, was bought for $8.3m (£6.2m) by the rare stamp dealer Stanley Gibbons at auction last month. For nearly a century and a half, the stamp has been held in collections abroad, but it will now go on display at the Stanley Gibbons flagship store in central London. Gibbons said gram for gram, the stamp is thought to be the most valuable manufactured item in the world, about 2.5m times more valuable than 24-carat gold. Security surrounding the stamp is tight. It will be flown into Heathrow and met by an armoured truck, before being driven to the showroom, where it will be stored in a vault before going on display in a specially commissioned, zero-oxygen frame. The octagonal stamp, printed in black on magenta paper and measuring 29 x 26 mm, features a three-masted sailing ship, as well as the motto “Damus Petimus Que Vicissim” which translates to “we give and expect in return”. The merchant said it is drawing up plans to make the stamp available to collectors through a shared-ownership scheme, suggesting shares in major paintings can sell for as little as £20. Graham Shircore, chief executive of Stanley Gibbons, said: “The British Guiana 1c Magenta really is the holy grail of philately. “It’s truly one of a kind, and we’re delighted to be welcoming it back on to British soil where we hope it will remain. “In the coming weeks we look forward to announcing bold plans, which will allow everyone to own their own piece of its marvellous history. This isn’t just for wealthy collectors. We are developing a pricing model that will allow anyone to join the club and look forward to announcing more details soon.” The stamp was previously on display at the Smithsonian National Stamp Museum in Washington DC, on loan from its former owner, the American shoe designer Stuart Weitzman. Its previous 12 owners include the French government and the philanthropist John du Pont, whose murder of the American Olympic gold medallist David Schultz was the subject of the 2014 movie Foxcatcher. Since 1873, each of the former owners has marked the back of the stamp, starting with noted stamp collector Philipp von Ferrary. The stamp is the only survivor of a small batch printed on the former British colony British Guiana – now the nation of Guyana – in 1856 after a ship from England that was thought to be delivering 50,000 stamps arrived carrying only 5,000. The postmaster ETE Dalton authorised the publishers of the Royal Gazette newspaper to carry out a small print-run of stamps, ordering each stamp to be signed off by a clerk to prevent forgery. It is understood the surviving stamp was used to deliver a newspaper that lay forgotten until 1873 when it was found by a 12-year-old Scottish schoolboy, Louis Vernon Vaughan, among his uncle’s papers, Gibbons said. He sold it for six shillings to a local collector.