There may be a listing of obsolete chips that are no longer redeemable, but probably not a list of "active" chips. Even if there was a list of active chips, many of them would no longer be in circulation at the casinos anyway, and this sounds like what you're looking for. The $1 Margaritaville chip from the Flamingo comes to mind as an active chip that is "extinct". I'm sure there are many more $5 limited edition chips that, while active, are either extinct or certainly on the endangered species list. Happy hunting.