An 1875 reissue of the 1861-1867 90c blue is valued at up to $275,000 ahead of Matthew Bennett International's February 25 sale in Maine.
The stamp is considered among the finest specimens of its kind. It displays a well centred print with superb margins and a minimal cancel.
The auction house comments: "If one had to select a single stamp that would exemplify the excitement and challenge of collecting used United States stamps, this high value re-issue would certainly be the first choice for most.
"It is the rarest regularly issued postage stamp in used condition, that is reasonably available mint, and has therefore earned its place as the Holy Grail for the used collector."
Another 1875 reissue of the 1861-1867 series, this time the 10c green, carries an estimate of $125,000.
Matthew Bennett International comments: "The 10 cent re-issue used is second only to the 90 cent of the same issue in regards to being fairly available in mint condition, but virtually impossible to obtain used."
The present lot displays a cork cancel and is in extremely fine condition.
The sale consists of highlights from the Michael Bakwin Collection, which includes more exceptional used US issues.