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Chrysoprase and Prase Opal from Haneti, Central Tanzania
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.

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Gem-Quality Yellow-Green Haüyne from Oldoinyo Lengai Volcano, Northern Tanzania

Yellow-green to green-yellow gem-quality haüyne was found for the first time in an alkaline plutonic rock.

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Hackmanite/Sodalite from Myanmar and Afghanistan

Significant amounts of gem-quality sodalite/hackmanite—some unusually transparent—have been produced.

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Rubies and Fancy Sapphires from Vietnam
Rubies and Fancy Sapphires from Vietnam

Gem-quality rubies and pink to purple sapphires are being recovered from the Luc Yen and Quy Chau mining regions of Vietnam.

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Reflectance Infrared Spectroscopy in Gemology

External reflectance infrared spectroscopy permits a very rapid and nondestructive determination of the species of a mineral.

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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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Amethyst Mining in Brazil

Brazil is currently the leader in overall production of amethyst.

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The Sapphires of Penglai, Hainan Island, China
The Sapphires of Penglai, Hainan Island, China

The sapphire deposit at Penglai, on Hainan Island, is potentially the largest in China.

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Gem-Quality Green Zoisite

A new transparent, gem-quality green zoisite has been discovered in the Merelani Hills of mineral-rich Tanzania.

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Sunstone Labradorite from the Ponderosa Mine, Oregon

The Ponderosa mine is now producing commercial quantities of the gem-quality labradorite feldspar known as sunstone.

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