Exonumia is the study of coin-like objects such as token coins and medals, and other items used in place of legal currency or for commemoration. more...
This includes elongated coins, encased coins, souvenir medallions, tags, badges, counterstamped coins, wooden nickels, credit cards, and other similar items. It is related to numismatics, and many coin collectors are also exonumists.
The noun exonumia is derived from two classical roots: exo, meaning "out-of" in Greek, and nummus, meaning "coin" in Latin; thus, "out-of-coins". Usually, "exonumia" is the term applied to these objects in the United States, while the equivalent British term is paranumismatica.
Items such as bus tokens (transportation tokens), bar or pub tokens, and casino tokens or chips are some of the more common forms of exonumia.
The words exonumist and exonumia were invented in July 1960 by Russell Rulau, a recognized authority and author on the subject, and accepted by Webster's dictionary in 1965.
Related, but normally considered to be a different branch of numismatics, is odd and curious money.
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