Regarding the discussion on dog license tags:

The master work, "U.S. Dog License Tags and Related Exonumia," is by William J. Bone, D.V.M., a very personable and knowledgeable guy. He published a limited number of copies in 2005.

This collecting field is evidently popular. A check on eBay showed hundreds of offerings, with many tags dating back decades. Information available on Web sites includes the datum that dog licensing goes back at least to the 1400s in Europe, though metal tags came along later. Some of these tags are colorful or unusual in shape. Like coins, they usually carry dates. They also bear local place names.

An interesting question is whether rabies vaccination tags, equally interesting, also qualify as exonumia. In many or most cases, these probably represent fulfillment of a legal obligation and payment of a fee, at least to a veterinarian. The number of place names multiplies by the number of local veterinarians.

To read the earlier E-Sylum article, see:ARE DOG LICENSE TAGS EXONUMIA?(www.coinbooks.org/esylum_v15n02a09.html)