Envelope, 1855, 10¢ green on buff, die 1, entire cancelled by fine strike of "Bison" (Skinner-Eno PA-Dr 13) and addressed to East Chester N.Y. at the 10c transcontinental rate, bold "Yreka Cal. Apr 15 1858" cds; lightened stain and reduced at top, no flap, Fine and rare, the Bison is not normally seen used as a cancellation; with 2010 P.F. certificate. Scott No. U16  Estimate $300 - 400. $0 (Image)