Hi Judy,
My husband and I bought a frame full of chips once. There were some very nice chips there, and we just hoped that they weren't glued to the black velvet that they were on. When we opened the frame, there was no glue yaaaaaaaay!! But, the inlays on a few of the chips had leeched some of the dye out of the fabric. Four of the chips are shown below. Thankfully, the Lady Luck inlay was o.k., as it was one of the more valuable chips in the frame...the inlays on the other 3 chips should also be white.

A few of the people on the board have said that the darkened inlays were probably caused from exposure to the sun, and the frame was opened and the chips turned around before we bought it. The sun may cause the same type of color change...but, in this case, I'm convinced the darkened inlays were caused by fabric dye.