An 1864 Goliad, Texas 10c Black on Buff Type II cover has top performed at the Peter Sharrer Collection of Confederate Postmasters' Provisionals.
One of just eight known examples of the stamp, of which only five were used on covers, it had come to the December 10 New York auction with a $40,000 estimate.
It quickly surpassed that figure, eventually realising $110,000 - a gain of 175% on the valuation.
While its rarity was a key factor, the stamp's large margins were also a major draw for buyers, with a light fold to the envelope and a small missing area of backflap its only detractions.
The result meant that a Livingston, Alabama 1861 5c Blue cover, which had been expected to lead the sale, had to be content with second place, despite, as we predicted, it beating its $60,000 estimate handsomely.
Its superb quality - including full to huge margins and vibrant colour - and great rarity proved irresistible to collectors,the lot selling for $100,000, 66.6% above the valuation.
The auction house called it "a striking pictorial stamp that depicts the southern shield and allegorical figures," adding that it is "one of the most outstanding of all confederate covers."
Its provenance also added to its appeal, having been bought by famed investor and stamp collector Bill Gross in 1999.
Gross sold it to Sharrer for $160,000 in 2009, evidence that even established collectors can pay over the odds for a specimen.
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