Iolite

Iolite is a gemstone that belongs to the cordierite mineral family. It exhibits a unique property known as pleochroism, where the gem appears to be different colors when viewed from different angles, typically shades of blue and violet. This characteristic, along with its transparency and hardness, makes iolite a popular choice for jewelry making.

Properties and Characteristics

Iolite has a chemical composition of Mg2Al4Si5O18, indicating it is a magnesium aluminum silicate. It ranks 7 to 7.5 on the Mohs scale of hardness, making it sufficiently durable for most types of jewelry. The most desirable color of iolite is a deep, vivid blue to violet, often compared to the sapphire, but it can also display lighter blues and grays. The gem's pleochroic nature means it can show up to three different colors (usually blue, violet, and yellow-gray) depending on the angle of view and lighting conditions.

History and Lore

The name "iolite" comes from the Greek word "ios," meaning violet, a reference to its most admired color. Historically, iolite is believed to have been used by Vikings as a navigational aid. They used thin slices of the gem as a polarizing filter to determine the exact position of the sun on overcast days, a technique that helped them navigate the seas.

Sources

Iolite is found in several locations around the world, including India, Sri Lanka, Myanmar (Burma), Brazil, Tanzania, and Madagascar. The quality of the gemstone can vary significantly from one location to another, with some mines producing stones that are more intensely colored or clearer than others.

Uses

Beyond its use in jewelry, iolite has limited industrial applications. Its pleochroic property has been explored for potential use in optical devices, but this application is not widespread. In the realm of metaphysical healing, iolite is said to enhance intuition and aid in understanding and releasing the causes of addiction.

Care and Maintenance

Due to its hardness, iolite is relatively resistant to scratches, but it can be damaged by sharp impacts. It is recommended to clean iolite jewelry with warm soapy water and a soft brush. Ultrasonic and steam cleaners should be avoided as they can cause damage to the stone.

See Also

• Gemstone
• Pleochroism
• Mohs scale
• Sapphire