I am a little confused because I often see numbers I don't recognize used to reference casino chips. Given that I use "The Official US Casino Chip Price Guide", my thought is these numbers are in reference to chips in the book, "The Chip Rack". The main question I have is what the major differences are between the two. Are the values and rarity for each chip the same in each book? While some may have one book but not the other, what are some suggestions as to how to best communicate? The numberic references are lost on me. Thanks!