Okay, so I'm on a roll! More ideas were rolling through my mind as to how else to make glass magnets. I recalled some of the smaller stamps that are now retired, and thought I would give this method a try. Not a good idea.
I used the smaller glass beads here, and after stamping the images I die cut them using the smallest of the circle framelits.
Then I followed similar steps to the other magnets I made (but I did not make a backing).