1893, 8¢ Columbian, printed on both sides, o.g., never hinged, clear impression on reverse, Very Fine, a rare variety, due to the controversy of whether it is a true error, it is being offered on its own merits; with 1979 P.F. certificate stating "it is a genuine variety printed on both sides".; with 1979 P.F. certificate. Scott No. 236  Estimate $200 - 300. This variety was discovered on one sheet in the 1970's. It has been argued by some that the impression on the reverse is a secondary or right reading offset while others believe it must be a true printed on both sides variety. $0 (Image)