I just discovered something that to me is quite a revelation.
If you may recall, there was a little thread about the McCarran SPADES awhile back...some collectors wondering about the origins of why or how it was minted in the first place. Most people are in the belief that it is simply minted with the SPADES instead of the HEARTS. It looks like it is much more than that.
Take a look at the following eBay auction and scroll down to see the sample page of the book they are selling. It describes the token in detail.
"Richard's Nevada Strike Book 2700+ Color Pics
Item # 2102833886". (I am not trying to sell the book or connected to it in any way.)
In short, it is actually similar to the GOLD RIVER/ISLE OF CAPRI error strike, in that one side is of a Nevada casino, and the other side is Non-Nevada.
I've admired mine more than a few times and never noticed...I guess my eyes were always riveted on the SPADES part and didn't pay much attention to the rim.