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 ...
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 ...
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 ...
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 ...
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 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 ...
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 ...
图 1:含有一种称作铁方镁石深色内含物的含硼蓝色钻石,作为此项研究的一部分进行了检测。这颗宝石重 0.03 克拉。摄影:Evan M. Smith(埃文·M.·史密斯)。 这是《自然》杂志中发表的文章 ...
To address concerns about laboratory-grown and treated diamonds being mixed into parcels of melee, GIA has developed an automated system to analyze and sort melee-size diamonds quickly and accurately.
A synthetic gem material is one that is made in a laboratory, but which shares virtually all chemical, optical, and physical characteristics of its natural mineral counterpart, though in some cases, ...
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 ...
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 ...