10c Ultramarine, Special Delivery, "Pink Back" (E11 var).
Mint N.H., intense color and impression on crisp paper, distinct pink tinge on back, Extremely Fine Gem, a superb example of this variety, with 2006 P.S.E. certificate (XF-Superb 95 Jumbo; SMQ as normal stamp $290.00 as 95, $630.00 as 98), footnote in Scott states "extremely scarce and valued higher than the normal stamp"
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