When it comes to the subject of cleaning older obsolete chips, I have found that it's just about split down the middle, between those who chose to clean and those who don't.Some people say that cleaning a chip "removes the history", I say that it removes the grime! If I have a chip that really looks bad from all the grime it has picked up in the casino, I will clean it. Too much grime on a chip will hide the true colors of the chip. Cleaning it and then applying a very small amount of mineral oil to the chip will bring the colors back.
If you do decide to clean some of your chips, make sure and read the information linked below. My friend and fellow club member, Charles Kaplan, compiled it a couple of years ago. Then The Casino Chip and Gaming Token Collectors Club listed the information on a page of their Web site.
http://www.ccgtcc.com/cleaning.html
