A Status Report on Gemstones from Afghanistan

An overview of the plentiful and various gem materials being discovered and produced in Afghanistan.

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Pink Diamonds from Australia

The author reports on a sudden influx of natural fancy pink diamonds and their origins.

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Sapphires from Australia

An overview of Australia's recent significance in the production of blue sapphire.

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Gem Pegmatites of Minas Gerais, Brazil: The Tourmalines of the Governador Valadares District

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Pearl Fashion Through the Ages

A history of pearls in jewelry and fashions through the ages.

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Pyrope-Spessartine Garnets with Unusual Color Behavior

Unusual color-change garnets.

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An Extraordinary Calcite Gemstone

The unusual effects of dispersion and twinning produced by a calcite gemstone.

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Gem-Quality Red Beryl from the Wah Wah Mountains, Utah

The unique mineralogical and gemological character of gem-quality red beryl from Utah.

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Natural Rubies with Glass-Filled Cavities

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Freshwater Pearls of North America

The American freshwater pearl industry and its new entry, the freshwater cultured pearl.

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Gem Pegmatites of Minas Gerais, Brazil: The Tourmalines of the Araçuaí Districts

First in a series, this article reviews the exploration for gemstones and mining methods in Minas Gerais, Brazil.

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Gem-Bearing Pegmatites: A Review

A survey of the current gemological knowledge of pegmatites, including the gem varieties aquamarine, tourmaline, and topaz.

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The Early History of Gemstone Treatments

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'Cobalt-Blue' Gem Spinels

Similarities between natural spinels — with intense blue color — and synthetic material, have led to difficulties in the recognition of the natural stones by traditional methods.

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ビルマのルビー:モゴック鉱区についてのレビュー (英語)

A review of the history of this area, its geology, and the mining methods that have predominated.

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Cobalt Glass as a Lapis Lazuli Imitation

The properties of a novel gemological imitation, cobalt glass.

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The Ramaura Synthetic Ruby

A report on the new synthetic ruby trade-named Ramaura.

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The Oil Treatment of Emeralds in Bogotá, Colombia

This article focuses on Colombian emeralds and gives a detailed explanation of the oiling process as observed by the author.

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Kashmir Sapphire

The history of the Kashmir mines, the beautiful sapphires found there, and the outlook for the future.

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Art Deco: The Period, the Jewelry

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