A look at the history of analytical instruments used for gem testing. UV-Vis-NIR spectroscopy measures how gemstones absorb and interact with light across the ultraviolet, visible, and near-infrared ...

如果您出生于六月，那么您很幸运，可以拥有三种生日石。六月是仅有的三个有三种生日石的月份之一（另外两个月份是八月和十二月），让您有各种各样美丽的生日石可以选择。 六月生日石是珍珠、亚历山大变石和月光石。有这么多吸引人的选择，六月生日的 ...

GIA studied more than 400 important gemstones from the Gübelin Collection and is committed to sharing this repository of gemological information. This work is a valuable resource for all students, ...

Figure 1. Two different types of Japanese hyalite rough specimens under daylight (left) and short-wave UV light (right). The photo on the right demonstrates the strong yellow-green fluorescence of ...

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, ...

亚历山大是一种美丽、稀有且坚固的宝石。 - ©美国宝石研究院 (GIA) & Tino Hammid（蒂诺·哈密德），由 Watt Gems（沃特宝石）的 Simon Watt（西蒙·沃特）友情提供 硬度和韧度 莫氏硬度用以衡量宝石和矿物的硬度。 这些数字基于一种矿物可被其他物品划伤的相对难易 ...

三月的两种生日石海蓝宝石和血石在外观上有着很大的差异，但在庇佑人们幸福安康这方面，二者都享有盛誉。海蓝宝石生日石让人想起大海的颜色。从深绿-蓝到淡弱绿蓝色的色彩，刻面海蓝宝石通常没有内含物，如水般清澈，象征着精神和灵魂的纯净。

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 ...

Established in 1931, the Gemological Institute of America (GIA) is the world’s foremost authority on diamonds, colored stones, and pearls. A public benefit, nonprofit institute, GIA is the leading ...

Cultured pearls come in different sizes, shapes, and colors. Perhaps the best-loved gems of all time, pearls—both natural and modern cultured pearls—occur in a wide variety of colors. The most ...

Fine-color, large, and eye-clean (lacking visible inclusions) rubies like this 11.01carat (ct) stone from Myanmar (formerly known as Burma) are extremely rare and valuable. – Photo: Robert Weldon/GIA.

The September birthstone is sapphire – a gem that’s been cherished for thousands of years. Although the term sapphire usually refers to the blue variety of corundum (ruby is the red variety), this ...