A 1907 Panama Canal Zone 2c carmine red & black invert stamp is expected to make $7,500-10,000 at Kelleher Auctions.
The lot will lead the Donald A Kuske Specialized Collection of Canal Zone: Stamps and Varieties, Postal History and Postal Stationery in Connecticut on September 9.
Kelleher explains the stamp is "considered to be one of the great rarities of Canal Zone. Plass records only 9 examples, all used and 'apparently defective'. This stamp would be one of the nicer examples."
Other lots on offer include a 1904 1c green invert overprint stamp that carries an estimate of $4,000-6,000.
Kelleher comments: "One sheet of 100 received the inverted overprint, but only six examples have been recorded, at least five and possibly all are used."
It's described as being in very good condition aside from a minor perforation repair.
A 1904, 8c on 50c bister brown, "P NAMA" variety stamp is likely to prove another highlight, with an estimate of $2,500-3,500.
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