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Opal

Fireworks. Jellyfish. Galaxies. Lightning. Opal’s shifting play of kaleidoscopic colours 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-colour displays the entire spectrum over a light grey background.

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Pattern

Bright flashes of colour 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-colour results when light interacts with orderly stacks of spheres.

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Treasure

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

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Tools

Research

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 have entered the market.

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Bursts of yellow and purple radiate throughout this round-cut ametrine.
Article
Colourblocking: The Art and Fashion of Multicoloured Gemstones

The fashion trend of colourblocking can be found in the artistic combinations of colour in multicoloured gemstones known for their colour zoning or banding.

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

Nature gives us a brilliant palette of colour-changing leaves and a spectacular kaleidoscope of colourful sunsets during the autumn season.

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Spring 2000 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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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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These two opals were represented as natural-color blue and pink opal from Mexico.
Update on Dyed Hydrophane Opal

Opal purportedly from a new deposit is found to be dyed.

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Article
2017 Las Vegas Trade Patchy, Designers and Diamonds Lead

Designers respond to market trends; demand for diamonds better than expected. Plus: Holiday season diamond marketing campaign gets funding boost.

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Ethiopian precious opal showing chatoyancy.
Flashes and Flames in Ethiopian Opal

Chatoyancy, rarely seen in play-of-colour opal, is observed in Ethiopian material.

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Opal slices before and after water immersion
Hydrophane Opal Treatment

An opal rough is immersed in water and treated with oil and Opticon to observe effects on transparency and play-of-colour.

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“Queen Thai” bracelet with fire opals.
New Designs from Paula Crevoshay

World-renowned jewellery artist Paula Crevoshay displays some of her newest pieces at the Tucson gem shows.

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