Thank You, the reason I said measure to see if they were all the same size size (molded) was a suspicion that perhaps some other method was at hand. I did not see seams as you usually do on the "light bulb" beads but this could be from age, wear, or way they are made. Perhaps the air bubble also give a hint at how they are made-maybe. I have lots of these beads, and some are stone, some glass, and some are odd..Going to go back and take another look with NEW EYES!
Thanks, Anne