A 1919 Newfoundland "Hawker" 3c brown sold for £16,000 ($24,846) in Spink's February 25 sale of pieces from the Lionheart collection of British Empire stamps in London.
The lot was issued for the flight of Australian pilot Harry Hawker, who was among the first to take up the Daily Mail's £100,000 non-stop transatlantic flight challenge.
Unfortunately technical difficulties with his aircraft led to his crashing in the sea 14 hours into the flight. Luckily, a passing ship (The Danish Mary) picked him up.
He died two years later in another crash at the Hendon aerodrome in London.
The stamp is marked "FIRST TRANS-ATLANTIC AIR POST, April, 1919" and features the initials of local postmaster JA Robinson on the reverse.
The condition is described by the auction house as "very fine unmounted mint". An 1863-1864 Cape of Good Hope 6d block of 18 proved another highlight, achieving a final bid of £10,000 ($15,533).
The value was introduced specifically to facilitate mailing mail to the UK and remained in production until 1900.
The Cape remained a British colony until the early 1900s, when it became part of the Union of South Africa.
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