Prime picture: T. gibbosula and C. rustica shells found in layer 4c from the cave in Morocco, which had been beads from precisely what is now generally known as the oldest jewelry in the world. Source: A. Bouzouggar, INSAP, Morocco / The shell beads also present insights into technological features https://medium.com/@spoilmevintagediy/the-rich-history-of-beadwork-a-journey-through-the-ages-4e4fd2e474cf