A 158-year-old stamp is set to go under the hammer at Sotheby’s New York this month where it is expected to fetch $20 million.

The Unique British Guiana 1856 One-Cent stamp, printed on magenta surface-colored paper, is currently on display at the exclusive auction house’s London branch before going on sale in the US on June 17.

Billed as ‘the world’s most valuable stamp’, the piece was first purchased either on or before April 4, 1856. It was discovered by 12-year old schoolboy Louis Vernon Vaughan in 1873, as part of his uncle’s stamp collection.

It was sold later that year and turned up in Paris in 1878 before being passed on to Austrian nobleman Count Philippe la Renotiere von Ferrary, a famous stamp collector. In 1922 ‘the world’s rarest stamp’ was sold for a record amount of $32,500.

It went under auction again before finally breaking a new record in 1980, when John E. du Pont paid $935,000.

The iconic talisman is now returning to the market, and Sotheby’s predicts that it will sell for anywhere between $10 million and $20 million.