The beads signify various and sundry things. Here are some brief descriptions. Green malachite - spacers. These beads go between the other beads, so they don't look like they're being crushed. Lapus Lazuli - year beads.
New members get two, then one additional bead for every full year.
Copper - First Circle status in the ADF Study Program. Silver - Second Circle status in the ADF Study Program. Gold - Third Circle status in the ADF Study Program. Amethyst - Member of the Bardic Guild . Red carnelian - Member of the Warriors' Guild .