The Pan-American Exposition
was a World's Fair held in Buffalo, New York,
from May 1 through November 2, 1901. A beautiful series of bi-color engraved stamps were
issued on May 1, 1901, in six denominations ranging from 1c to 10c, by the US Post Office
to commemorate the Pan Am Exposition.
Today I received this 1902 registered cover mailed from San Francisco to Saginaw Michigan.
It has the 1c, 2c, and 4c Pan American Exposition stamps neatly applied to a Columbian 5c
stamped envelope. The 4c shows an electric automobile in Washington.
It is hard to imagine someone who was not stamp collector or dealer creating this cover.
A little bit of googling revealed that E. F. Gambs was a stamp dealer in San Francisco.
A close-up of the stamps shows they are a little toned around the perfs.
Anyone ever tried to remove a little toning from stamps on a cover?
My inclination is to not try it.