If the material is porous (like, say, clay), then the oil will absorb into the chip. Obviously, the surface will dry first. I oiled a few rolling edges of my Pharoah's Club chips, but that was all.
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Much more likely to fully oil casino chips, especially hot stamps. I may oil the rest of the edges on my Pharoah's Club chips, but probably not. Wiped the dust with a dry rag and off they went into play..