seal (device)

A seal is an impression printed on, embossed upon, or affixed to a document (or any other object) in order to authenticate it, in lieu of or in addition to a signature. Only in the case of a dry seal the imprint is made as a relief resulting from the greater pressure on the paper where the high parts of the seal touch; in all other cases a liquid or liquified medium (such as ink or wax) is used, allowing the choice of another color than the paper's.
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