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Alexandrite

Green in sunlight. Red in lamplight. Colour-changing alexandrite is nature’s magic trick.

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Chrysoberyl Variety

Alexandrite is the colour-change variety of the mineral chrysoberyl.

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Green by Day

Alexandrite is bluish green in daylight or fluorescent light.

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Red by Night

Alexandrite is purplish red in incandescent light or candlelight.

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Star-shaped Twin

This alexandrite specimen is made up of three interpenetrant crystals.

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Brazilian Gem

Brazil is one of the most important alexandrite sources.

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Re-entrant Angle

Notches marking the edge of each crystal are called re-entrant angles.

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Tools

Research

Alexandrite cabochon in fluorescent (left) and incandescent light (right).
Cat’s-Eye Alexandrite with Unique Inclusion Pattern

Examination of a chatoyant alexandrite cabochon.

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Three pieces of labradorite with yellow, blue and green flashes of color.
Article
Optical Effects of Phenomenal Cabochons

Learn how the structure, inclusions and properties of some gemstones interact with light to create unusual visual effects.

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Spring 2004 Gem News International

A compilation of gem news from around the world, covering topics such as localities, unusual gem materials, market news, new products, discoveries, jewellery manufacturing techniques and industry trends.

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Mohs Scale
Article
Alexandrite Care and Cleaning Guide

Learn about alexandrite's durability and how to care for your alexandrite jewellery.

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Alexandrite
Article
Alexandrite Quality Factors

Learn about the factors that make alexandrite so desirable.

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Worker attaching wax forms
Article
Shenzhen: The Frontier of China’s Gem and Jewellery Industry

All jewellery professionals are familiar with the city of Shenzhen, a global jewellery manufacturing centre and a leader of China’s fast-growing gem and jewellery industry. Join the GIA team as we tour the city and discover more about its leading jewellery brands.

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Article
Gemmologist’s Black Opal Ring Wows Consumers and Trade Media

GIA graduate Niveet Nagpal, president and head designer of Omi Privé, showcases his love of gems and brings them to life in his designs.

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Article
The Glory of Green Gems

Green gemstones, which can uplift and heal our spirits, have been popular gem choices ever since we began to adorn ourselves with jewellery.

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Article
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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Brecciated Pyrite
Spring 1991 Gem News International

A compilation of gem news from around the world, covering topics such as localities, unusual gem materials, market news, new products, discoveries, jewellery manufacturing techniques and industry trends.

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