It's like that all over the world; we see chips surfacing 120 years after a casino closed that we never knew existed previously. The only thing I'm unsure of is the different Bunny hot stamp which doesn't match the other hot stamps. Somebody in Chicago may know for sure, though. That's where I got the BJ Training School chips from; a lead from a girl who saw them on an executive's desk... I called Tom and he was shocked... Even ex-house employees had no idea the chips existed.