オークションハウス:強力な市場が主要なダイヤモンドと色石宝石に影響を及ぼす (英語)

A report on how high-profile jewelry auctions have affected the gem and jewelry market.

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Enriching a Tradition

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Infrared Spectroscopic Study of Filled Moonstone

A study on how infrared spectroscopy provides conclusive evidence of impregnated moonstone.

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ムンバイの研究室に提出された3つのCVD(化学蒸着)合成ダイヤモンド (英語)

The gemological and spectroscopic characteristics of these type IIa synthetic diamonds suggested that they experienced different growth and/or treatment histories.

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CVD成長法によって作られた非常に大きい合成ダイヤモンド (英語)

The New York laboratory recently tested a 2.16 ct CVD synthetic from Scio Diamond Technology Corp., the largest specimen GIA has seen so far.

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塊状の窒素不純物を含むCVD成長合成ダイヤモンド (英語)

Recently, an unusual 0.94 ct Fancy yellow-brown emerald cut was submitted to GIA for a synthetic diamond grading report. It contained a cloud of black needle-like inclusions occurring along a plane and showed weak green transmission with fiber-optic illumination.

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大きいCVD合成ダイヤモンドの未開示の試料 (英語)

In mid-2012, one of the international diamond grading laboratories in Antwerp reported undisclosed CVD synthetic diamonds, causing a stir in the diamond industry.

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Rare Double-Trapiche Emerald

At the AGTA show, Equatorian Imports showed this contributor two pieces of emerald with a very rare double-trapiche pattern

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Musgravite from Myanmar

Two small, near-colorless stones reportedly from Myanmar were loaned to GIA for examination.

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Blue Cat's-Eye Apatite

Deep blue apatite with a cat’s-eye effect, however, is very rare.

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Dumortierite-Quartz Rock Presented as Sapphire

The Gem Testing Laboratory of Jaipur, India, received for identification an opaque blue specimen, submitted as sapphire.

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Green Diamond, Treated with Radioactive Salt

The stone owes all of its green color to these shallow radiation stains.

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A Comparison of Modern and Fossil Ivories Using Multiple Techniques

This article provides identification criteria to distinguish between modern and fossil (mammoth) elephant ivory.

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Gemological Characteristics of Saltwater Cultured Pearls Produced After Xenotransplantation

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An Opal-Calcite Composite

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