Pieters & Co., 4¢ Black, Silk Paper, remarkably well centered especially for this tight margin issue, rich color on fresh paper, small thin, otherwise Extremely Fine, a truly wonderful example of the extremely rare Pieters & Co. 4¢ Black on Silk Paper, with only 10 examples recorded in the Aldrich census (of which 7 are reported to be faulty); with 2012 P.F. certificate. Scott No. RS191b  $6,000. It is noted in the Aldrich book that well centered examples of the Pieters & Co. 4¢ black on silk paper are virtually non-existent. $0 (Image)