Jim wrote... But regardless of how they turn up, there are enough of theses to indicate that although each one may be unique to the casino, in the overall, this type of error is not all that uncommon.

While what you said is exactly accurate, these chips with identical sides when they are supposed to be different, truely are 1 of a kind for each example. Based on what I've seen in Archie's book and I think one on ebay, they sell for between $400 - $500 - but I haven't seen the latestest AC book.

IMHO, to call them "not uncommon" would make it sound like you can find one without any problem at all? I think someone once explained how these errors occur during productin and I've been told there is usually a match with the other one being 2 sided opposite.

I don't think anyone has ever reported finding more than 1 of the exact same error for the same chip?

So I think they really are a nice find and something unique to have in any collection. One like this from the Hard Rock would fetch 4 figures easily.

Scott