Iolite Gemstone Variety of Cordierite
Iolite is the gemstone variety of the mineral cordierite. A translucent stone with distinctive bluish violet colour, it's often compared to sapphire but has more of a purple tint. One of the most notable characteristics of iolite is pleochroism. Pleochroism is an optical phenomenon that enables a crystal to exhibit different colours when viewed from different angles. Depending on the type of light and angle from which the stone is viewed, it can look blue or a subtle shade of violet. As the stone is is rotated the colour changes to yellowish grey to light blue.
The name iolite comes from the Greek word 'ios' meaning violet whilst cordierite was named after the French geologist Pierre Louis Antoine Cordier who first described the mineral in 1809. Iolite was officially classified and named as a gemstone in 1813 but is believed to have been known and used in Sri Lanka long before that.
Although many other gemstones are pleochroic, unlike iolite most have such minimal colour change that it's almost unnoticeable. Cordierite and tanzanite are the two main minerals which exhibit pleochroism with colour change that can be easily seen. Although two completely different minerals, iolite can sometimes be confused for tanzanite which is the gemstone variety of the mineral zoisite. Although their optical characteristics are similar, tanzanite is much rarer and considerably more expensive.
More Facts about Iolite
The finest iolite crystals come from from India, Brazil, Sri Lanka, Mozambique, Zimbabwe, Madagascar and Myanmar. It's widely believed the stone was also mined by the Vikings in Norway and Greenland. More recently in 1996 an iolite deposit was found in Wyoming in the USA and further discoveries were made in 2004 and 2005.
In crystal healing iolite is used to clear thoughts, it opens intuition and aids in understanding and releasing the causes of addiction. It can help to release conflict and tension within a relationship and will encourage you to take responsibility for yourself by becoming more independent.
Graded 7 to 7½ on Mohs scale of mineral hardness means iolite is a relatively hard stone which makes it particularly suitable for faceting.