Allan;
I looked at this chip carefully, below is a scan of the 3 different Little Caesars chips that I picked up at the same time. The hot stamp on the mustard chip is deeper and cleaner. There is no indication of foil on either side that I can see with my magnifying lens. Maybe it is a hot stamp that went wrong somehow. I do have quite a few chips with the where the H/S has worn and a yellow color is shown, this is really different.

I guess the only way to really determine is to see this chip in person. Because the scan really does not do it justice. Thanks for your consideration, just trying to help you with additions to your book.

Best Regards
Michael Petty