You're buying the story, not the bead. The Uses of Beads Wampum . It never was. It was white man's money. See Wampum .
Most stories are pure fiction.
They have them in use from the American Southwest through the Northern Plains to the Northeast. They catch bad dreams and don't let them reach you. They allow bad dreams to escape. They catch good dreams and let them reach you. They catch good dreams so you can hold on to them.