Rarely some Iolite display a Four rayed star and are cut en-cabochon, which are extremely rare –– a collectors gem.
Extreme Pleo chroism - is the property which made iolite so valuable to the Vikings. Iolite comes in different colours in different directions in the crystal. An Iolite cube will look violet blue, like Tanzanite from one side, colorless from the other, and a yellow from top.
