when i opened my bead shop in the '80s/90s there were so many loops of the badly drilled agate beads coming out of India -called Beggar beads, on thick nylon fishing line- nothing else would go through.
usually a mix of shapes- square sections, rounded tapered triangular sections and roundish
with thread "knots" between. they did not include the crisply faceted ones in your first messages though, which i feel are european, and older...