This is a system for balancing magic based on two negative aspects: A) Magic creates “noise” that those sensitive to power will notice and B)Magic is channeled through rifts to other parts of reality OR other dimensions/planes/what have you and those rifts can get out of control…
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!