A 3d Baden-Powell pale blue on blue stamp issued during the 1899-1900 siege of Mafeking has sold for £35,000 ($56,674) at Spink.
The lot led the sale of the Harry Birkhead collection in London on March 12, which featured a range of philatelic items from the era of the Boer War (1899-1902).
Only 10 copies of the rare reversed design are known to exist, three of which are in mint condition and housed in the permanent collections of museums.
The other seven are used, including this example, which is the finest of the five in circulation on the private market.
It was produced during the siege and features an image of Robert Baden-Powell, the town's garrison commander and future founder of the scouting movement, making it the only British empire stamp not to feature the monarch.
During the siege, Baden-Powell founded the Mafeking Cadets Corps - a group of young boys charged with delivering post and carrying out various duties in support of the soldiers defending the town.
He published Scouting for Boys in 1906 on his return to Britain from South Africa and held the first camp on Brownsea Island in Poole in 1907. Today the organisation has 38m members in 161 countries.
We have a range of rare stamps available, including this 1901 £5 Orange issued in Britain while the Boer War was raging in South Africa.
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