Demonetize

Demonetization is the declaration that a stamp issue is obsolete and has no value and thus no longer valid.

To Americans, this is more common than you might think. While Brits in 2023 experienced the obsolescence of old definitves, the last time stamps were demonetized was during the conversion to decimal currency back in the 1970s. Americans can still use most every stamp issued since its Civil War. Elsewhere, currency/banknotes/bills along with stamps can be demonetized, either due to a currency revision or just a regular change made to discourage forgery. In the 19th Century, Spain and its colonies and Portugal and its colonies issued new definitive stamps after a year or two for some time, with the previous issue becoming obsolete.

"How do it know?" You have to be aware of post office announcements. The Michel catalogs are good at noting dates when issues have become obsolete.

So not only be wary of stamps offered as postage supposedly offered at face value or less, as well as currency being offered for exchange when travelling abroad. 



[[Category:D]]