I had heard about this chip before but thought is was probably a process error in printing the inlay. I saw it at the Convention and now I'm not so sure. One side has what appears to be an optical distortion of the name "Riviera".

The other side has a white dot in the center (part of the inlay, not raised on the chip) just where the graphic artist might put a circle to help him form the leg of the "R" properly. There's what looks like a center-punch mark on the chip rim above the shield. That same side has some black smudge across the inlay but it carries over to the chip rim, and there's no black in the printing process, so I think it's just dirt.

This is probably intended to be N3934. I'm going to call it an error, but I don't know how it came to be. The punch mark could be to identify it as defective, but sure looks like it made it into play. The Chip is well used.