I picked these up at a yard sale for 1 clam each. I do not collect them but figured I might be able to sell or trade them off for dice. The one with white on brown has concentric circles in the bottom. The clear lettering on brown has a plain clear bottom. The one with Caesars head on the bottom has no paint anywhere. Anybody know what they are worth? The guy I got them from said they are from the 80s but I know nothing about ashtrays.