CARLSBAD, Calif. – January 29, 2025 – GIA field gemologists recently completed their one-hundredth expedition, adding to the Institute’s unrivaled store of independently verified gemological ...

Pietersite has been described as a brecciated variety of tiger’s-eye. This study examined pietersite specimens from Namibia and China (the main sources) using powder X-ray diffraction, optical ...

Figure 1. This alexandrite cabochon appears brownish green in fluorescent light (left) and brownish purple in incandescent light (right). The cabochon shows chatoyancy under both forms of illumination ...

Jade is one of the most misunderstood gemstones. It is actually two separate materials: jadeite and nephrite. Together, these materials have more simulants than most other gems. Thus, it is important ...

Metrology, the science of measurement and its application, plays a critical role in the accuracy of GIA’s research and laboratory services. The metrology team closely monitors the performance of ...

With decades of expertise and laboratory locations worldwide, GIA uses more advanced instrumentation that extends far beyond the boundaries of standard gemological testing. The comprehensive analysis ...

Secure your spot for the Sept. 7-10 event in Carlsbad, CA CARLSBAD, Calif. – January 27, 2025 – Registration for Converge, the singular gem and jewelry event combining the unique expertise of the ...

美国宝石研究院 (GIA) 在线教育包含在线课程和实习班，可助您获得 GIA 课程文凭。完成三门专业发展课程后，即可获得应用珠宝家 (Applied Jewelry Professional) 文凭。您可通过在线课程灵活学习 ...

However gem quality diamonds are fashioned from the original crystal shape they possess a combination of brightness, sparkle, fire, and sense of purity not matched by other gems. - Jeff Scovil, ...

该杂志创立时较为简陋。 GIA 和出版物的创始人 Robert M. Shipley 在家中发行了第一期杂志。 他和他的儿子 Robert Jr. 写了很多的文章，而 Shipley 的妻子 Beatrice 则是业务管理员。 Shipley 对于出版物 ...

This 5.30-carat emerald from Brazil has a slightly bluish green color. Courtesy John Parrish, courtesy African, Brazilian, Colombian Gems Incorporated. Emerald has many special qualities, but colored ...

Due to the overwhelming popularity of GIA’s limited time, no-charge offer, all GIA Essentials classes starting in May and June – the period of the offer – are full. The offer is closed and we cannot ...