If you left it in the sun, wouldn't the whole chip turn brown?

After looking at a normal Turning Stone $1 up close maybe it had something to do in the finishing process of the chip that made it discolor. If somebody didn't do something to this chip to make it look like it is then nobody really noticed until now when Travis got it.

They have been in play since 6/5/98 (8 years is a long time to float around a casino without notice).

Dave R-6620