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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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Gemology (6)
History (3)
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Education (1)
Geology (1)
Inclusions (1)
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Organics (1)
Physical properties (1)
Quality Factors (1)

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

C. B. Dissanayake and M. S. Rupasinghe, September 1, 1993

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

Peter C. Zwaan, June 1, 1982

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

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Gubelin Cordierite - Iolite 34802 300x169
Article
GIA's Gübelin 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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With proper care, iolite jewelry will provide a lifetime of beautiful adornment. – Robert Weldon
Article
Iolite Care and Cleaning

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

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Iolite has a long history of use as an adornment and possibly as a navigation tool. – Robert Weldon
Article
Iolite History and Lore

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

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The color of fine-quality iolite can sometimes rival that of sapphire or tanzanite. – Robert Weldon
Article
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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The cutter took full advantage of this iolite’s color and transparency, fashioning it into a uniquely carved gem, ready for use in jewelry. – Lydia Dyer, Gem courtesy John Dyer & Co.
Article
Iolite Quality Factors

Learn about the factors that make iolite so desirable.

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