GIA’s laboratory in Bangkok, Thailand conducts research and provides services such as diamond grading and origin determination, colored stone grading and origin determination and pearl identification ...

Demantoid, green andradite garnet, was discovered in the Central Ural Mountains of Russia in the mid-19th century. A favorite of the Czar's court, demantoid was another victim of the 1917 Bolshevik ...

This article traces the use of pearls from antiquity to the initial appearance of cultured pearls in the 1920s. The first section touches on the early fascination with pearls as revealed through ...

The People's Republic of China has recently placed a high priority on identifying and developing its gemstone resources. Initial exploration by teams of geologists throughout China has identified many ...

Jewellery Arabia is the Middle East’s premier jewellery and watch event. Backed by a 30 year track record of success, this five-day show unites the world’s most desirable brands and extraordinary ...

Synthetic diamond growth was first documented in 1952 by William Eversole of the Union Carbide Corporation, but it took another two decades before GIA issued the first grading report for a ...

The Chinese have labored to perfect the art of gemstone carving for several thousand years. Beginning with primitive tools and limited materials, they eventually developed the iron-tipped spindles and ...

Surface-treated topaz has become a viable alternative to topaz colored by irradiation. Unlike irradiation, which modifies the entire gemstone, coloration by chemical modification is limited to the ...

The green turquoise cabochon, from an American mine, might become part of a designer’s unique jewelry piece. The even blue color of the cabochon on the right would be called “Persian blue” in the ...

Jadeite comes in a wide range of colors. The most valuable is an intense green called Imperial. - Courtesy Mason-Kay Fine Jade Jewelry To understand the value of jade, you have to look beyond its ...

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 ...

祖母绿用于首饰已有几个世纪的历史。 有了适当的保养，现代珠宝镶嵌的祖母绿同样可以代代相传。 — Color Masters 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 ...