On the Origin of Digit Patterns in Gem Opal

An examination of the finger-like feature mostly found in Ethiopian opal, and proposal for its formation.

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スリランカ:宝石の島への探検旅行 (英語)

Offers a firsthand look at Sri Lanka’s mining, cutting, jewelry manufacturing, and retail sectors, where tradition and innovation converge.

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Supporting the Researchers of Tomorrow

An overview of the Fall 2014 issue of Gems & Gemology, as well as GIA’s efforts to promote gemological research.

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Xenotime Inclusion in Yellow Diamond

Presents what is believed to be the first report of a xenotime inclusion in gem-quality diamond.

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Natural Pearls Reportedly from a Spondylus Species (“Thorny” Oyster)

A rare look at natural pearls from a known Spondylus species, commonly called “thorny” oysters.

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二つのファンシーダークグレーCVD合成ダイヤモンド (英語)

Examination of two CVD synthetic diamonds with an unusual Fancy Dark gray color.

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Flame-Fusion Synthetic Ruby Boule with Flux Synthetic Ruby Overgrowth

This synthetic ruby specimen features two growth methods within the same crystal.

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珍しいインクルージョンのあるCVD合成ダイヤモンド (英語)

Examination of a CVD synthetic diamond with an unusual pattern of growth dislocations that resemble natural inclusions.

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強く照射処理されたCVD合成ダイヤモンド (英語)

A look at the first CVD synthetic diamond examined at GIA that has been irradiated to a blue color.

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コロンビアのエメラルド採掘:巨大鉱山は目覚めるか? (英語)

Overview and commentary on the 2013 The Journal of Gemmology article “Peñas Blancas: An Historic Colombian Emerald Mine."

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“Red” Chrysoberyl versus Alexandrite: The Impact of Elevated Chromium Levels on Color and Color-Change Properties

Overview and commentary on the 2014 Journal of Gemmology article “Purple to Reddish Purple Chrysoberyl from Brazil.”

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Pleochroism in Faceted Gems: An Introduction

Describes the phenomenon of pleochroism and its complex effect on the appearance of colored stones.

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Observations on Pearls Reportedly from the Pinnidae Family (Pen Pearls)

Examines the internal structure, chemical composition, and spectroscopic features of 22 pen pearls.

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Nephrite Jade from Guangxi Province, China

Introduces the Chinese nephrite mine in Hechi and characterizes the “band” and dendritic patterns found in this material.

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Books: Unique by Design: Contemporary Jewelry in the Donna Schneier Collection

Review of Suzanne Ramljak's Unique by Design: Contemporary Jewelry in the Donna Schneier Collection.

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Books: Ruby & Sapphire:A Collector’s Guide

Review of Richard Hughes’s Ruby & Sapphire: A Collector’s Guide.

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書籍:Kentucky Agate: State Rock and Mineral Treasure of the Commonwealth(ケンタッキー州産アゲート(瑪瑙/めのう):州指定の岩石および鉱物の財宝) (英語)

Review of Ronald McIntosh and Warren Anderson's Kentucky Agate: State Rock and Mineral Treasure of the Commonwealth.

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Books: Jewels of the Romanovs: Family & Court

Review of Stefano Papi’s Jewels of the Romanovs: Family & Court.

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Aquamarine with Unusually Strong Dichroism

This aquamarine's most striking feature was its unusually strong dichroism, displaying very deep blue and pale bluish green colors.

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Color-Change Garnet in Diamond

The Indian Gemological Institute’s Gem Testing Laboratory recently examined a 0.30 ct colorless round brilliant-cut diamond containing an interesting inclusion.

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