Glass beads are a very old art form, going back 3500 years. Here is a sample of forms across the century, courtesy of the Corning Museum of Glass. Because beads are almost always used in groups, the techniques of their manufacture have to be easily repeatable -- it's no good making one bead, you need dozens and preferably thousands. Above, composite eye bead from Carthage, 600-250 BCE.
So even complex designs like these have to follow from fairly simple recipes: lay glass rods of different colors like this, bend, twist, cut, things like that. So similar-looking forms recur across the millennia, and around the world. Kiffa bead from Mauritania, 1980s.
Necklace of drawn beads from Malaysia, 200 to 799 CE.
Chevron bead from Venice, 17th century.
Necklace of glass pendants and beads, Greece, 1400-1250 BCE.