

Bicolor Double-Eye Tourmaline
A tourmaline displaying different colors of chatoyancy on opposite sides of a double cabochon is examined.

Unusual Pink Sapphire Bead
A pink sapphire bead with drill holes revealing ruby fragments is examined.


Iridescent Musgravite
A musgravite specimen’s inclusions result in an optical phenomenon unusual for the material.

Blue Chalcedony Partially Filled with Epoxy Resin
A carving identified as blue chalcedony shows evidence of epoxy resin treatment.


Dual-Color Double Stars in Ruby, Sapphire, and Quartz: Cause and Historical Account
Examines a form of asterism comprising two six-rayed stars, one white and one that exhibits the stone’s bodycolor. Firsthand accounts and a survey of patent documents reveal that diffusion has been used to create or enhance this optical phenomenon in synthetic and possibly natural corundum since the 1950s.

Digital Photomicrography for Gemologists
A guide to capturing gem inclusion scenes using practical equipment and techniques and the appropriate image-refining software.

Rubies and Sapphires from Snezhnoe, Tajikistan
This large marble-hosted occurrence in the Pamir Mountains is a potentially productive source of corundum, including ruby with a bright red color reminiscent of “pigeon’s blood” Burmese rubies.

Introduction to the Micro-World of Gems
G&G’s new column takes a closer look at the hidden wonders found in gemstones.

Books: Imperial Jade of Burma and Mutton-Fat Jade of India
S.K. Samuel著 Imperial Jade of Burma and Mutton-Fat Jade of India: Mining, Trade, and Use from Antiquity to the Present(ビルマのインペリアル ジェードとインドの羊脂玉:採鉱と売買、古代から現代までの用途)の書評

Books: I Love Those Earrings: A Popular History from Ancient to Modern
Review of I Love Those Earrings: A Popular History from Ancient to Modern, by Jane Merrill with Chris Filstrup.


Books: Collector’s Guide to the Zeolite Group
Review of Collector’s Guide to the Zeolite Group, by Robert J. Lauf.

Books: Imperial Jade of Burma and Mutton-Fat Jade of India
Review of S.K. Samuels’s Imperial Jade of Burma and Mutton-Fat Jade of India: Mining, Trade, and Use from Antiquity to the Present.

3Dプリント:GIAが学生に「テクノロジー革命」に備えるべく指導
時間、精度、費用対効果についての評価に重点が置かれるジュエリーのデザインと製造において、3Dプリントが持つ可能性は驚くべきものです。

源流へのロマン:アフガニスタン
GIAのフィールド宝石鑑定士と共に、アフガニスタンのパンジシール渓谷にあるエメラルド鉱山への本格的な宝石採掘の冒険に出かけましょう。この地の屈強な住民たちは、ソ連による10度もの侵攻を撃退してきました。これまでほとんど誰も目にしたことのない、山岳地帯のエメラルド採掘現場をご覧ください。


コランダムにおける合成ルビーのオーバーグロースの分析
インクルージョン分析、UV-Vis-NIRおよびエネルギー分散型蛍光X線組成分析法、レーザーアブレーション誘導結合プラズマ質量分析法を用いた、コランダムにおける合成ルビーのオーバーグロースの分析。

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