A US 24c Inverted Jenny error could set a new record for a single US stamp at auction next month.
The prized item - the highest graded unhinged example of the 100 in existence - will star in a single lot sale at Spink New York on May 21 with an estimate of $1m.
The stamp is the most recognisable error in American philately, and the few surviving specimens are highly prized among collectors.
This example is known as the JE Safra holding, and was bought by the philatelist for $173,000 at Christie's New York in 1994.
The stamp was created in 1918 for use on the newly implemented airmail service between Washington DC, Philadelphia and New York.
It is estimated there were around four sheets that featured the invert, three of which were destroyed.
The one remaining sheet was bought by a collector in a post office and sold on a number of times before being broken up into blocks and singles.
The auction record for a single US stamp is held by another Inverted Jenny, which made $977,500 at Robert A Siegel in 2007.
Highly impressive figures have been continually set by the issue over the years. In 2005, noted collector Bill Gross paid $2.9m for a one of a kind block of four in a private sale.
More recently, a lesser example sold for $625,000 at Robert A Siegel.
We have our own world-class rarities on offer, including this unique 1865 Hong Kong 96c plate block of four.
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