Wampum was a symbolic, ritual object to the Iroquois.  It was exchanged during important peace and war pacts and treaties between tribes.  Wampum included a string or dense web of sinew or hemp fibers that is up to five inches thick that held the decorative beads.  It was worn around the waist or over the shoulders and chest as a scarf. 
They made the wampum from strings of purple, white, and black shell beads that were woven in symbolic patterns into belts and girdles.  The colors represented different things.  The white symbolized peace, and black meant sorrow.  Purple signified seriousness, and it was the most valuable color.  European settlers traded glass beads for wampum with the Iroquois, so the Iroquois started to use wampum for their advantage for the first time.