US Postage Due Stamps were authorized by Act of Congress on March 3, 1879, and they became effective on July 1, 1879.
Before the creation of postage due stamps, the amount of insufficient postage to be collected by the carrier was written by hand or hand-stamped on the front of the envelope. The new stamps were to be affixed by a postal clerk to letter mail, to indicate the amount to be collected from the addressee, resulting from the insufficient prepayment of postage by the sender.
The first batch of the postage Due Stamps was issued between 1879 and 1891 and was printed by the American Banknote Co. on unwatermarked, soft porous paper. The stamps were issued with the denominations raging from 1Cents to 50 Cents.
The common design of the stamps features the denomination value in the centre inside an oval vignette inscribed with “POSTAGE DUE” at the top and the denomination in words and the bottom. The Inscriptions are divided by letters “U” on the left and “S” on the right which stands for United States!
They came in two different colours. The stamps issued between the 1879 and 1890 were issued with different shades of light brown whereas the stamps from the 1891 printing are printed in claret shades.
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