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Opal

Fireworks. Jellyfish. Galaxies. Lightning. Opal’s shifting play of kaleidoscopic colors is unlike any other gem.

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Cabochon

Most opals are cut as cabochons; this one from Ethiopia weighs 20.86 ct.

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Unique Beauty

The play-of-color displays the entire spectrum over a light gray background.

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Pattern

Bright flashes of color skip across this stone’s surface.

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Hidden Beauty

Opal forms as irregular nodules or seams in volcanic or sedimentary rocks.

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Rare Phenomena

Play-of-color results when light interacts with orderly stacks of spheres.

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Treasure

This opal nodule displays the promise of intense play-of-color.

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Tools

Research

An oval shaped 33.40 ct white Australian opal and diamond pendant/brooch set in platinum.
Article
The Enigmatic Gemstone: Opal’s Playful Dance with Light

Opal’s play-of-color is a lyrical dance: sometimes a grand jeté of bold, broad flashes of color or smaller, quicksteps of pinpoint flashes.

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A large group of people outside on GIA’s Carlsbad, California  campus.
Article
Guardians of Trust: GIA’s Innovative Research, Instruments and Services

GIA’s services and instruments have grown in importance and impact as new gem treatments and laboratory-grown gems enter the market.

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Inclusions in Natural, Treated, Synthetic, and Imitation Opal

Provides a visual guide to the internal features of natural, treated, synthetic, and imitation opal.

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GIA field expedition team in Ethiopia
Land of Origins: A Gemological Expedition to Ethiopia

Documents a visit to the sapphire, opal, and emerald mining and trading areas of Ethiopia.

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Boulder opal with layer of lepidocrocite inclusions
Lepidocrocite in Boulder Opal

A boulder opal contained an unusual carpet of needle-like lepidocrocite inclusions along the interface between the opal and the ironstone matrix.

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A bright orange, multi-faceted gem.
Article
Fall for Autumn Gems

Nature gives us a brilliant palette of color-changing leaves and a spectacular kaleidoscope of colorful sunsets during the fall season.

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Bursts of yellow and purple radiate throughout this round cut amertrine.
Article
Colorblocking: The Art and Fashion of Multicolor Gemstones

The fashion trend of colorblocking can be found in the artistic combinations of color in multicolor gemstones known for their color zoning or banding.

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A view from behind of a bejeweled winged insect.
Article
A Glittering Garden: A Menagerie of Designs from Mother Nature

Delightful garden creatures and flowers are favorite subjects that transform beautifully into Victorian, Art Nouveau and modern jewelry designs.

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Mexican fire opal with good claritiy
Outlook on Opals from Mexico and Australia

Jürgen Schütz discussed the opal sourcing and cutting activities of the German firm Emil Weis.

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Indonesian opal cabochons, 6.94 and 3.79 ct.
Opal from West Java, Indonesia

Description of Indonesian opal reportedly from West Java.

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