In
philately
Philately (; ) is the study of postage stamps and postal history. It also refers to the collection and appreciation of stamps and other philatelic products. Philately involves more than just stamp collecting or the study of postage; it is poss ...
a backstamp is a
postmark on the back of a
letter showing a post office or station through which the item passed in transit.
The office of delivery may also backstamp a cover and this type of mark is known as a receiving mark.
Backstamps are often applied as documentation of transit times, lengthy ones in the case of ocean crossings or short ones in the case of
airmail flights.
Registered mail is often backstamped in order to show the
chain of custody.
Mail that has had complex routings can have a dozen or more backstamps. Although such covers may look positively blackened with the overlapping marks, they are not common and so are highly valued by collectors of
postal history
Postal history is the study of postal systems and how they operate and, or, the study of the use of postage stamps and covers and associated postal artifacts illustrating historical episodes in the development of postal systems. The term is att ...
, being described as "well travelled".
References
Philatelic terminology
Postal markings
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