Wikipedia - Exonumia are numismatic items other than coins and paper money. This includes "Good For" tokens, badges, counterstamped coins, elongated coins, encased coins, souvenir medallions, tags, wooden nickels and other similar items. It is related to numismatics, and many coin collectors are also exonumists.
So, where in numismatics does metal detecting lie? Oh, that's right! It is in the dirt and sand. Don't get me wrong, Mr. P. I like your threads about the things you find, but there are many more categories directly related to numismatics which should come first when considering the creation of a new forum. ~ Chris