Emeralds are again being mined in the historic district of the Ural Mountains. Physical, chemical, spectroscopic, and microscopic characteristics of stones from the recent production are presented and ...

This sapphire from Kashmir has an intense velvety blue color. – Photo: Robert Weldon/GIA. Sapphire is one of the Big three of jewelry colored gemstones—the other two are ruby and emerald. A durable ...

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 ...

Diamond is available in a range of sizes and qualities to fit every consumer's tastes. One of the first things most people learn about diamonds is that not all diamonds are created equal. In fact, ...

Because laboratory-grown diamonds are essentially chemically and optically the same as natural diamonds, traditional gemological observations and instrumentation are not able to tell them apart. GIA ...

莫氏硬度用以衡量宝石和矿物的硬度。 这些数值基于一种矿物可被其他物品划伤的相对难易程度得出。 但莫氏硬度会引起误导。 不同矿物的硬度等级之间的差距并不均匀。 举例来说，钻石的莫氏硬度只比刚玉高1度，但实际上它比刚玉家族的宝石坚硬好多倍。

The majority of saltwater and freshwater pearls bought and sold in the global jewelry markets are “whole pearls,” sometimes referred to as “cyst pearls” (CIBJO, 2017). These pearls form within the ...

Consumers now, more than ever, have a heightened awareness of sustainably and ethically sourced products. The GIA Diamond Origin Report uses scientific evaluation to provide confirmation of a ...

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 ...

As a consumer, you will regularly encounter in the marketplace gems that have been treated to change their appearance. A topic that often comes up is whether a particular gemstone is or isn’t treated.

有些软体动物（如牡蛎）生活在海洋和海湾等海水环境中，还有一些软体动物（如某些贝类）则生活在湖泊和河流等淡水环境中。生活在这两种环境中的软体动物体内都可能长出珍珠，但海水软体动物更具多样性。

You need to sign a client agreement every time a new version is published. If a new signed client agreement is required, a Client Service Representative will reach ...