You won't find spangles on any type of bobbin except the East Midlands English type. There are even English bobbins which don't use them - neither South Buckinghamshire types, nor Downtons, Malmesburys or Honitons have them.

The spangle was almost certainly invented from c.1760's onwards in England as an anti-swivelling device to prevent previously unspangled types of bobbins overtwisting (or untwisting) and spoiling thread which was now machine-spun instead of hand-spun. The entire question of when spangles were invented is bound up in the introduction of machine-spun threads in the English Industrial Revolution. They also act as an added weight (on slim lightweight English bobbins) to keep the threads straight and under tension. Although historically most of the beads used in them were made in the usual European glass beadmaking centres of Venice, Bohemia, France, etc., many others were actually made in England itself.

Carole