Hi Mary, in my experience some of the faceted Bohemian beads were used in the African trade so they show up on raffia sometimes. But the ones traded in the Pacific NW are usually on a simple cotton thread, sinew, horsehair, or modern collections strung on fishing line. People wander the banks of the Columbia River to this day gathering them, so I see a lot of them on fishing line. I live in Washington and find them semi-frequently, lucky me!

It seems to me that the African-traded beads are inferior in color and glass quality to those from the PNW, I don't know why. You get much more of a deep, indigo blue/purple with the American beads for some reason.

I think yours are probably from the African trade and so are the powder blue ones that were mentioned, which are also commonly found on raffia.