Cara Evelyn,
measures are not so accurate due to irregularity of the ends of the beads. However, minimum length 25 mm, maximum length 61 mm; width varying from 14 to 19 mm; conisder that also in this case width varies in the same segment. I was told that the knots one can observe in some beads should be part of bridges between galleries, a sort of pillars.
Ciao, Giorgio