Mel Jung would know more about the Harrah chips. I thought he said the only way they could confirm they were fraudulent was to take them apart and thus destroying the chips. Certainly only a handful of chips have ever been detected to defraud the casinos. I'm sure due to security issues it's not something a casino want's to publish openly. It's probably not worth the effort to defraud the chip collectors. Too much trouble for what it's worth...