After my post with the pictures of the new O'Shea's chips, my father asked me via email about the colored sections along the edges of the chips. I told him that I didn't know much about that, except that they are called "inserts" by chip collectors, and apparently make the manufacturing process more difficult to duplicate by would-be counterfeiters. He replied, "I have the impression that for the same chip design, the edge markings might vary from day to day or week to week, maybe. In most of the chips I’ve seen in your blogs the edge markings seem to be pretty irregular and sometimes somewhat sloppy."
The edge spots, or inserts, are not painted on; to achieve this effect, this area of the clay is removed and then replaced with clay of a different color; this can be done to each chip individually or a strip can be taken out of a cylindrical block of material and replaced with the alternate color before the block is cut into chips.