Iolite is an unusual gem that is quickly gaining popularity. It has a strong blue to bluish violet colour. It has very strong pleochroism, which means the stone appears different colours depending on the direction you’re viewing it from. It is a very good and more affordable alternative to tanzanite, a stone with which it is often confused. In fact its superior hardness and durability makes it a better stone than tanzanite for rings and other jewellery items that are exposed to wear and tear. There are no treatments for iolite.