EXTREMELY FINE GEM. A BEAUTIFUL AND RARE USED EXAMPLE OF THE 1895 6-CENT WITH THE "R" OF "USIR" WATERMARK. ONLY 27 USED EXAMPLES ARE KNOWN TO US, AND THIS IS ONE OF THE FINEST IN EXISTENCE.
The "USIR" (United States Internal Revenue) watermark error occurred when a supply of paper reserved for revenue stamp production was used for printing the 6c and 8c postage stamps. Unlike its more common 8c counterpart, the 6c is an extremely rare stamp. Our census of this issue, available at http://www.siegelauctions.com/dynamic/census/271a/271a.pdf , records only 24 used copies certified as genuine by The Philatelic Foundation, plus three uncertified copies. Fifteen of those certified do not specify which letter is present. The other twelve are split exactly equally between the "I" and "R" of the watermark. Many examples have perfs either close or touching the design.
Census No. 271a-CAN-08. Ex Hoffner, Rubin and "Natalee Grace". With 1988 P.F. and 2009 P.S.E. certificates (XF 90; SMQ $30,000.00). This is the highest grade awarded and the only example to achieve this grade.