The modern elephant, threatened by extinction, is protected by international agreements banning the sale of ivory from tusks. This trade ban does not apply to ornaments made of mammoth fossil ivory, ...

Four similar-appearing yellowish green samples from Block D at Merelani, Tanzania, were identified as diopside and tremolite. The gems are identical in color, but their standard gemological properties ...

Studies carried out at the DTC Research Centre have shown that single-crystal CVD synthetic diamond is clearly distinguishable from natural diamond. This article presents information about the CVD ...

Figure 1. The largest known natural moissanite crystal, found along the Kishon River in northeastern Israel, measures 4.1 mm in its longest dimension. Photo by Vered Toledo. Synthetic silicon carbide ...

Twenty-six peridot samples from the Esquel pallasite meteorite and 27 samples from 10 terrestrial sources were studied by laser ablation–inductively coupled plasma–mass spectrometry (LAICP- MS). Among ...

Vivid blue, green, and purple-to-violet cuprian elbaites, renowned in the gem trade as “Paraíba” tourmalines, continue to be recovered in small amounts from northeastern Brazil. Since the initial ...

GIA Student Workrooms give you affordable access to all the equipment and gemstones you need to complete the practical requirements of your Gem Identification course through Online Education. This ...

GIA Student Workrooms give you affordable access to all the equipment and gemstones you need to complete the practical requirements of your Gem Identification course through Online Education. This ...

Twelve natural-color purple diamond crystals from Siberia, and seven round brilliants that were faceted from some of these crystals, were studied using spectroscopic methods to better understand their ...

GIAの学生用ワークルームでは、オンライン教育を通して学ぶ宝石鑑別コースの学生が実技必修科目を修めるために必要となるあらゆる装置や宝石を手軽に利用することができます。20個の石 ...

This course covers how to describe diamond jewelry accurately for effective and ethical sales conversations with customers. Key topics examined include the internationally accepted GIA clarity grading ...

このコースでは、ダイヤモンド ジュエリーの販売に際し顧客と効果的に倫理観を持った会話ができるように、ダイヤモンド ジェリーを正確に説明する方法を学びます。主要な課題は、国際 ...