Two Australian rough diamonds demonstrate both pink and colorless sections in the same crystal.

A rare chatoyant effect is produced within play-of-color patches in a natural opal.

The Carlsbad laboratory recently examined an unusually large faceted hexagonite with iridescent cleavage cracks and needle-like structures.

An overview of the Spring 2021 Gems & Gemology content.

Presents a method for accurately predicting the color of a gem material when viewed in any direction as long as the polarized spectra and the viewing angle relative to the c-axis are known.

Presents the internal characteristics of natural P. maxima pearls, obtained from real-time microradiography (RTX) and X-ray computed microtomography (µ-CT) analysis of 774 samples.

Provides a visual guide to the internal features of natural, synthetic, and treated spinel, as well as inclusions of spinel in other gemstones.

Oblique fiber-optic illumination of thin-film fluid inclusions in Brazilian aquamarine reveals a kaleidoscopic play of interference colors.

In a delightful juxtaposition, a diamond-shaped cloud inclusion appears in the center of a 0.53 ct round brilliant diamond.

Attractive iridescence creates a beautiful “play-of-color” effect on dendritic healed fissures in a blue sapphire.

The Carlsbad laboratory recently examined a Mexican opal containing a rare fluid inclusion with a freely moving gas bubble.

A singly-terminated topaz from Pakistan hosts a prominent phlogopite crystal with strong dichroism and lamellar cleavage planes.

The author examined a 0.56 ct Fancy grayish bluish green diamond with prominent green radiation stains.

A centuries-old diamond featuring a hand-drilled hole inspires an investigation of the briolette cutting style and the history of drilling diamonds.

The Chinese jewelry industry bounces back quickly due to the country’s incredible digital ecosystem and the uptick in sales at international luxury brands.

An overview of the Spring 2021 Gems & Gemology content.

Two cabochons displaying white four-rayed “stars” are fashioned from one large natural diamond crystal.

加利福尼亚州卡尔斯巴德 — 2021 年 5 月 17 日 — 越来越多仿冒 GIA 天然钻石报告刻字的实验室培育钻石提交至 GIA 鉴定所进行更新或验证。

CARLSBAD, Calif. – April 20, 2021 – Inspiration is a driving force in all of our lives, and it was the deciding factor in the difficult decision to select just two recipients for the Beyoncé Knowles-Carter x Lorraine Schwartz GIA Scholarship for full tuition to earn GIA’s Graduate Gemologist diploma through distance education.

加利福尼亚州卡尔斯巴德— 2021 年 4月 14 日 — 比利时某法院引证认可 GIA 提供宝石证书服务和教育，明确命令以 American International Gemological Laboratories（美国国际宝石实验室）和 Antwerp International Gemological Laboratories（安特卫普国际宝石实验室）之名运营的比利时 AIG 立即停止单独使用“AIG”或与其他标志连用，否则将面临巨额罚款。