A 5c Greenville provisional issued in Alabama in the 1860s will lead a sale of Civil War and Confederate States stamps in New York.
It was introduced following the invalidation of pre-1861 stamps by the Union states at the outbreak of war.
Local postmaster Benjamin F Porter designed the 5c Greenville provisional
The recall caused a flowering of philatelic creativity in the south, surviving examples of which can be valuable today.
A judge and local postmaster named Benjamin F Porter was behind this design.
It may be a humble regional provisional, but as Siegel explains: "Postmaster Porter's typeset provisional issue is not only very rare, it is remarkable as one of three postmaster issues printed in two colors - the others were issued at Baton Rouge and Lenoir.
"These are the first government-issued, bi-colored adhesive postage stamps to appear anywhere in the Western Hemisphere."
Only six examples remain, of which four are loose and two are attached to covers.
As an added marker of this stamp's importance, it was formerly in the collection of the wildly eccentric Colonel Green (1868-1936), one of America's greatest stamp collectors.
The lot is expected to sell for up to $25,000 when it crosses the block at Robert A Siegel on June 22.
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