Official State Stone or Gem of Idaho
The star garnet was designated the official state stone or gem of Idaho in 1967. More precious than either star rubies or star sapphires, the Idaho garnet is usually dark purple or plum in color, with four rays in the star (occasionally the star has six rays, as in a sapphire). All State Gems
The mountains of Idaho contain veins of gold, silver, lead, zinc, cobalt, copper, and many other rare minerals - among these rare minerals are gems like the star garnet, jasper, opal, jade, topaz, zircon, and tourmaline.This is why Idaho's nickname is "The Gem State."