KacheKat & Kickin' (Antique Silver)
This is the personal geocoin of Pennsylvania geocachers KacheKat and Kickin'. They were released sometime around May 2006 in possibly four flavours, or maybe just three, of which I think the shiny nickel (aka polished silver) is the regular edition, and the only trackable version. There was a 3-coin LE set that included "one silver trackable, one LE nickel non-trackable, and one LE gold non-trackable."
So, I've got an antique silver non-trackable, and a polished nickel/silver trackable. (That I know of... there could be a third geocoin around here somewhere.) Oddly, the non-trackable coins still have the text saying they are trackable on geocaching.com.
Size: 42.5 mm, 50 mm including spikes