The glass is 3/16" thick. The cup weighs close to 1/2 lb, with perfect heavy overlay, and reacts strongly to a black light. I suspect the punch cup blanks are early 1930s Czech with U.S. overlay. Thickness of glass and all polished panels indicate Czech blanks; that was not unusual in the 30s. Rockwell used Czech blanks from time to time, but the decorator of this piece is unknown.