The position 76 Inverted Jenny, one of America’s most famous errors, is coming to auction at Robert A Siegel in New York.
In 1936 the stamp was part of a block of four sold to a Mrs Ethel McCoy for $16,000.
However, in 1955 the block was stolen while being shown at the American Philatelic Society convention in Norfolk, Virginia.
Someone attempted to disguise the reverse of the stamp
It was presumed lost forever until a young Northern Irish consignor approached Spink for a valuation last year.
The auction house went to Siegel to confirm that this was position 76 (albeit altered slightly in an attempt to avoid detection).
The stamp was found with a receipt suggesting that it might have passed through the hands of SH Engel & Co., a stamp trading firm run by the notorious fraudster and fence John A Fox, in the early 1960s.
After that the trail goes cold.
Kieran O’Neill, the prospective consignor, explained: “My grandfather gave me a box of stuff two months before he passed away.
“I wasn’t aware I actually had a stamp in there. He never really pointed out to me what it was.”
O’Neill is unsure exactly where the stamp came from, but thinks his grandfather might have unknowingly picked it up in a job lot at a car boot sale.
He said: “Once I was told that it was stolen, I wanted to give it back to the rightful owner.”
Mrs McCoy had left the stamp to the American Philatelic Research Library (APRL) in her will, and so it was returned to the organisation.
The APRL presented O’Neill with a $50,000 cheque at the New York World Stamp show as a reward for returning the Jenny.
The lot is now expected to make $450,000 in the May 11 sale.
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