The Iolite is a beautiful and unique stone where at first glance is a violet or purplish-blue color, but because of its unique property referred to as pleochroism can appear violet blue from one side, clear from the other, and golden yellow from the top. Because of this property, Iolite was used to help guide the ancient Vikings on the seas. By peering through a thin disc of Iolite the Vikings were able to determine the exact position of the sun because of the shifting color of the gem.