Are you familiar with "black lights"? Ultra Violet or UV lights? They come in a variety of sizes and packaging, but many chips, especially the ones you are showing here, also have UV tags. Sometimes done to show manufacturer and sometimes done as a security measure, but either way it adds a new dimension to one's collection.

For example, the Gold Coast chip, if I remember correctly, might have the date of manufacture printed on the inlay. The Wynn chip repeats the name, over and over and over. Some will reveal the manufacturer's logo, a hat and cane for Paul-Son, which seems to be all of them, except for the Hilton, which is Paul-Son's sister company, Bud Jones.

Jim