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.

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.

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

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

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

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

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

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

An overview of how GIA's instrument development helped gemologist identify gemstones

Shipley 为何及如何建立 GIA 及其使命

通用电气 (GE) 公司生产第一批合成钻石至今已近 60 年，他们对珠宝市场产生了巨大影响。

探讨这一技术在映射缺陷和光谱特征、确定颜色成因，以及鉴定合成和经处理的米粒钻方面的有效性。

Explores the fascinating history of natural pearling in Australian waters and examines the properties that might help distinguish these natural pearls from those that are accidentally produced during the culturing process.

A relatively new source of gem-quality turquoise is hosted within slates in Zhushan County of China’s Hubei Province.

Natural-color saltwater cultured pearls (SWCPs) from Pinctada maxima were studied using UV-Vis-NIR and PL spectroscopy to better understand the mechanisms of their coloration and to separate them from other SWCPs with similar natural colors.

This article describes the major gem materials of Vietnam, together with their new finds and recent production.