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Iolite

According to legend, Vikings used iolite slices to reduce glare when checking the sun’s position.

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Pleochroism

Iolite displays different colors when viewed in different directions.

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Transparency

Iolite is usually faceted to highlight its transparency.

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Fine color

Iolite’s finest blue color can rival tanzanite’s vivid hue.

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Fashioning

Iolite’s pleochroism can be a challenge for cutters.

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Natural

Iolite is not treated for color enhancement.

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Cordierite

The mineral cordierite is known as iolite in the jewelry industry.

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Tools

Research

A Prospectors’ Guide Map to the Gem Deposits of Sri Lanka

Sri Lanka is world famous for its gem wealth, but the actual extent of the deposits has never been determined.

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Sri Lanka: The Gem Island

An overview of the many types of gem-quality material, and its inclusions, currently found in Sri Lanka.

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Iolite Care and Cleaning

Learn about iolite's durability and how to care for your iolite jewelry.

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Iolite History and Lore

Iolite has a long history of use as an adornment and possibly as a navigation tool.

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Iolite Description

This silicate of aluminum, iron, and magnesium has two distinctive features—a beautiful, violetish blue through slightly violetish blue hue derived from iron and a striking, eye-visible pleochroism.

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GIA Gem Project
Various Gems (Barite - Cuprite)

Among the collection assembled by Dr. Edward Gübelin are a number of uncommon gemstones from many worldwide localities.

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Iolite Quality Factors

Learn about the factors that make iolite so desirable.

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