When was the last time you truly used, focused on, for any significant length of time, your imagination; your active, conscious, willful, artistic creativity, to get back in touch with that ability to appreciate the wonder that you yourself can create and bring forth, all from within yourself? Were you ever able to do that? Did you ever do that? Can you still do it? Do you do it when you game, as player or GM? Will you do it? Could this be missing from a lot of the newer, younger RPG'ers of today?
Orcish currency is derived from glass beads. The art of glassworking is well beyond them, but perhaps the orcs have something of value to the civilized races, such as animal pelts, and well made axes, and bows. The humans trade beads for the goods, and the orcs will trade the beads amongst themselves as a form of their own currency. Perhaps they value blood red beads above all others, or animistic orcs favor beads in the colors of their gods.
Inspired by Indian trade beads, some of which could be quite ornate and beautiful. Most North American Indian beads were made in Italy. Surprise!