JETON \JET.un\ n. a coin-like token often used to represent money in casino games, dispensing machines etc; also JETTON
Hopefully you recall that numismatics is generally used to refer to the study or collection of coins. Strictly speaking, though, this word covers a great deal more than coins; it encompasses tokens, medals, bank notes, and pretty much anything related to currency.
Now if you just want to refer to the non-coin part of numismatics (especially the study of tokens, medals, and other coin-like objects), the correct word is EXONUMIA (literally ‘without/outside coins’). A person who collects these sorts of items is called an EXONUMIST.
So it is the exonumist, rather than the numismatist, who is likely to have the most impressive jeton collection.