Pictorial cancellation

A cancellation (or cancel for short; French: "oblitération") is a postal marking applied on a postage stamp or postal stationery to deface the stamp and prevent its re-use. Cancellations come in a huge variety of designs, shapes, sizes and colors. Modern United States cancellations commonly include the date and post office location where the stamps were mailed, in addition to lines or bars designed to cover the stamp itself. The term "postal marking" sometimes is used to refer specifically to the part that contains the date and posting location, although the term often is used interchangeably with "cancellation." The portion of a cancellation that is designed to deface the stamp and does not contain writing is also called the "obliteration" or killer. Some stamps are issued pre-cancelled with a printed or stamped cancellation and do not need to have a cancellation added. Cancellations can affect the value of stamps to collectors, positively or negatively. The cancellations of some countries have been extensively studied by philatelists and many stamp collectors and postal history collectors collect cancellations in addition to the stamps themselves.

The first adhesive postage stamp was the Penny Black, issued in 1840 by Great Britain. The postal authorities recognized there must be a method for preventing reuse of the stamps and simultaneously issued handstamps for use to apply cancellations to the stamps on the envelopes as they passed through the postal system. The cancels were handmade and depicted a Maltese cross design. Initially, the ink used was red, but it was found that this could be cleaned off and the stamps reused, and so after a series of experiments, early in 1841 black cancelling ink was used, which was more permanent. The color of the stamps was also changed to red-brown so as to ensure that the cancellation showed clearly.

Britain soon abandoned the Maltese crosses and in 1844 began to employ cancellations displaying numbers which referred to the location of mailing. A similar scheme was used for British stamps used abroad in its colonies and foreign postal services, with locations being assigned a specific letter followed by a number, such as A01 used in Kingston, Jamaica, or D22 for Venezuela.

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