4c Columbian, Error of Color
(233a). Beautiful deep rich color in the more intense of the two error
shades, choice centering with wide margins, neat strike of duplex circular
datestamp and "2" oval grid, trivial crease and minor repair, accompanying
certificate (1973) remarks that shade has been affected by "aging", which
we feel is not at all the caseVERY FINE APPEARANCE. ONLY THIRTEEN USED EXAMPLES OF THE 4-CENT COLUMBIAN ERROR OF COLOR HAVE BEEN CERTIFIED BY THE PHILATELIC FOUNDATION. ONE OF THE GREAT RARITIES OF USED UNITED STATES STAMPS.
The 4c Columbian color error was caused by the use of a wrong batch of ink. Spectrographic analysis confirms that the ink of the 4c error matches that used for the 1c stamp. There are two recognized shades of the color error, one being slightly darker than the other. Of the thirteen used examples certified as genuine by the Philatelic Foundation, only half can be confirmed by us as being in the darker shade.
Only six of the thirteen stamps certified by the Philatelic Foundation are sound. One of these received two previous certificates as the Deep Ultramarine sub-shade of the issued stamp before being issued a third certificate as the error of color. Three of the other sound copies have not been re-examined for faults in more than 20 years. Therefore, the number of sound copies may actually be less than six. Most of the used examples are also off-center to some degree, with eight having the perforations either close or touching on at least one side. The stamp offered here is among the three best-centered of the group. If one takes into consideration the factors of both condition and centering, this stamp should be considered one of the most desirable used examples of this rarity.
With 1973 P.F. certificate (Image)