The legendary British Guiana 1c Magenta, the world's most famous stamp, has been certified by the Royal Philatelic Society.
The Expert Committee at the society held a special meeting to re-authenticate the stamp, with six experts and spectrometer analysis confirming its authenticity ahead of the dedicated auction through Sotheby's New York on June 17.
Having spent much of its life in private collections, particularly that of the infamous John du Pont, the stamp was last certified in 1935.
Despite its reputation, any serious collector would have winced at the thought of paying Sotheby's $10m-20m estimate without guarantee that this was the real deal.
"We deeply appreciate the Expert Committee at the Royal Philatelic Society convening a special meeting to review this extraordinary stamp," commented Sotheby's vice chairman David Redden.
"In the philatelic world, certification is considered best practice, as is modern day recertification using up-to-date connoisseurship and scientific techniques - a fascinating process that was an honour to witness with The British Guiana."
Chairman of the Expert Committee, Christopher Harman added: "It was a privilege to see in the flesh one of the great icons that every collector has heard about, returning nearly 80 years since the British Guiana's last visit with us.
"With more experience and advanced technology, the Expert Committee undertook a thorough examination and I am very pleased to say that the 'patient' passed with flying colours."
Collectors can view the British Guiana 1c Magenta on a global exhibition tour this spring:
- Hong Kong Convention & Exhibition Centre - April 3-7
- Sotheby's London - June 1-5
- Sotheby's New York - June 7-17
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