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Opals from Opal Butte, Oregon
Recent mining at Opal Butte in northeastern Oregon has produced a wide variety of large flawless opals.
Gemstone Durability: Design to Display
A treatise on the design, display, care and repair of fine gemstones.
Summer 1986 G&G Lab Notes
This section, from the Summer 1986 issue of Gems & Gemology, is a compilation of interesting finds from GIA’s laboratories.
Jewelry Television in Tucson
A look at JTV’s history, current activities, and impact on the industry.
Preview of Nature Art Science with Paula Crevoshay
Renowned designer Paula Crevoshay discusses artistic influences and her latest creations.
Written Characters in Black Opal
Play-of-color patches in black opal display interesting written character patterns.
Snowflakes in Opal
Chrysoprase and Prase Opal from Haneti, Central Tanzania
Commercial quantities of gem-quality chrysoprase and green prase opal (nickel-bearing chalcedony and common opal, respectively) have been recovered from altered serpentinite deposits near Haneti, Tanzania.
Winter 2011 G&G Lab Notes
This section, from the Winter 2011 issue of Gems & Gemology, is a compilation of interesting finds from GIA’s laboratories.
An Opal-Calcite Composite
Gem Testing lab in Jaipur, India recently examined a white-brown, translucent to opaque oval cabochon that turned out to be a composite featuring an unusual combination of gem materials.
Opal History and Lore
Writers have compared opals to volcanoes, galaxies, and fireworks. Admirers gave extraordinary opals poetic names like Pandora, Light of the World, and Empress.
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