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Dyed Purple Hydrophane Opal

Opals with an unusual purple bodycolour and strong play-of-colour have recently appeared in the market.

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Play-of-colour opal from Wegel Tena, Wollo Province, Ethiopia
Play-of-colour opal from Wegel Tena, Wollo Province, Ethiopia

A new opal deposit was discovered in 2008 near the village of Wegel Tena, in the volcanic rocks of Ethiopia’s Wollo Province.

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Winter 2011 G&G Lab Notes

This section, from the Winter 2011 issue of Gems & Gemmology, is a compilation of interesting finds from GIA’s laboratories.

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Abstract Header from the 2009 issue of Gems & Gemology
Abstracts; Summer 2009

This article, from the Summer 2009 issue of Gems & Gemmology, is a compilation of abstracts of important gemmology-related articles published outside of Gems & Gemmology.

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Gemstone Durability: Design to Display

A treatise on the design, display, care and repair of fine gemstones.

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Opal from Querétaro, Mexico: fluid inclusion study

The distinctive orange-to-red “fire" opals from Querétaro have not been found in significant quantities at any other locality.

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Green Opal From East Africa

Gemmological and chemical analysis of bright green gem-quality opal from Tanzania.

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New occurrence of fire opal from Bemia, Madagascar

Twenty-two gem opals from a new volcanic deposit located near Bemia

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Leopard Opal
Leopard Opal: Play-Of-Colour Opal in Vesicular Basalt from Zimapán, Hidalgo State, Mexico

“Leopard opal” consists of vesicular basalt impregnated with play-of-colour opal, and is known only from Zimapán, Hidalgo State, Mexico.

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Opals from Opal Butte, Oregon
Opals from Opal Butte, Oregon

Recent mining at Opal Butte in northeastern Oregon has produced a wide variety of large flawless opals.

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