Chihuahuas are believed to be decendents of an ancient breed, the techichi. Toltecs in Mexico kept these pups as lap dogs as early as the 9th century. Relative to their bodies, Chihuahuas have the biggest brain in the dog world. They're quick-witted and some pet parents would say they're little geniuses, :).
This is a fairly large pendant and looks fantastic designed into a longer necklace.