Adela is the currency of the Illph. The Adela is a system of beads rather than coins and are made out of various materials; the rarer/more valuable the material the bead is carved out of, the more it is worth. The beads are often kept on a string for easy portability.
Common materials for Adela beads include (from lowest to highest value): wood, animal bones/horns/teeth, and shells.
Less common (and therefore more valuable) materials for beads include: coral, copper, turquoise and other gems/stones, amber, silver, and ivory.