Ruby in zoisite is a rock that is comprised of 3 minerals: corundum aka ruby (red), zoisite (green), and hornblende (black). Corundum aka ruby has a hardness of 9 on the Mohs scale of mineral hardness. from the 6th century C.E. and mention Burma (still a main source).
Sources of zoisite include Tanzania (tanzanite), Kenya (anyolite), Norway (thulite), Switzerland, Austria, India, Pakistan, and the U.S. state of Washington.
