Well casino related, not chip.

Poker pro Phil Ivey must return $10 million won while edge sorting
http://www.mercurynews.com/2016/12/19/poker-pro-phil-ivey-must-return-10-million-won-while-edge-sorting/

About what it is. (which I never knew except trick cards when I was a kid)
https://en.wikipedia.org/wiki/Edge_sorting

Why would casinos use cards that can be distinguished from each other by the back design?