[Westbound Pony Express to Oregon], 10c Star Die entire addressed to Portland, Oregon, bold March 10 St. Joseph COCPP/PE green datestamp, manuscript $2.50 express charge, entered the mails at San Francisco for carriage onward to Oregon, their San Francisco Mar 25 1861 postmark, PF cert, 9 reported examples of this marking on westbound mail, rare use that entered the mails for carriage beyond California, PF cert, Frajola Pony Express census #W34, extremely fine

(MWE Figure 13-9), ex Dale Lichtenstein and Walske (Image)