Robert Eisenstadt's mold design project.

http://www.antiquegamblingchips.com/molddesignindex_site.htm

Click on #5 to find the Hub mold, you'll see that it was manufactured by the Mason Co. Howard Herz has acquired the old records from the Mason Co., so often the hub mold UFC's (Unidentified Flying Chips) can be identified.

Robert's site is a GREAT place to learn about chips!