A 1910-1913 £1 double head block of four is to lead a sale of Rhodesian stamps at Spink London on March 18 with a valuation of £40,000-50,000 ($61,414-76,767).
All the items in the sale are drawn from the prestigious Vestey collection, which includes some of the rarest and most desirable British Empire stamps in existence.
The lot is one of only two known specimens to feature the "gash in the Queen's ear" error, seen here on the top right.
The double head issue was released in 1910 and shows Queen Mary alongside King George V, in an impressive range of colour variations. It remains the most sought-after Rhodesian stamp among collectors.
Also included is a 1d double head block of eight, which carries an identical estimate of £40,000-50,000 ($61,414-76,767).
It's described as "a monumental rarity and one of the great highlights of the collection."
The auction house comments: "This remarkable sale is the second in the Lord Vestey series of auctions that feature Rhodesia.
"This sale devoted to the lovely Double Head issue is packed with fabulous blocks and single item rarities from the wealth of printings and shades associated with the issue…An outstanding offering for the specialist."
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