In 1977 when I was primarily collecting design clay and ivory chips, I bought two boxes of chips from a Mass. dealer. They contained a number of what Dale and I called "machined" chips. In the box were several chips from O'Dwyers in New Orleans. Most of the rest were stamped over and were obviously salesmen's samples. The person I naively thought to be the manufacturer was Frank W. Walters who, I believe, was doing business in the Detroit area. I have been told that the chips were produced by the Burt Co. but have no proof of that. Dale or Robert Eisenstadt may know. In any event, I have several of the "machined" or concentric circle mold chips with "F.W. Walters" or "F.W." on them. Once I get my scanner completely fired up, I'll post scans of some of them.