Top rated graphic: T. gibbosula and C. rustica shells found in layer 4c with the cave in Morocco, which were being beads from what exactly is now often called the oldest jewelry in the world. Source: A. Bouzouggar, INSAP, Morocco / The extreme hardness and brittleness with the materials made https://medium.com/@spoilmevintagediy/the-rich-history-of-beadwork-a-journey-through-the-ages-4e4fd2e474cf