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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 ...

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, ...

Diamonds have a long history as beautiful objects of desire. In the first century AD, the Roman naturalist Pliny stated: “Diamond is the most valuable, not only of precious stones, but of all things ...

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 ...

GIA has studied more than 400 important gemstones in the Edward J. Gübelin Gem Collection and is committed to sharing this repository of gemological information. Dr. Edward Gübelin’s lifelong study of ...

这颗 17.53 克拉的紫水晶展现出饱满的红紫色。 - Lydia Dyer（莉迪亚·代尔），超级三角形紫水晶宝石，由 John Dyer & Co.（约翰代尔公司）友情提供 数百年来，紫水晶一直是最有价值的石英类别。 它一度为皇室专有，而到了现代，相对丰富的供应让紫水晶更加普遍了。

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 ...

Figure 1. Russian demantoids are well known for their pure colors and remarkable inclusions. Photo by Kevin Schumacher. Russian demantoids (figure 1) are renowned in the gem community for their pure, ...

Ruby is the July birthstone – and it’s one of the most coveted of gems. The name is derived from the Latin word ruber, meaning “red” – the color of love and passion. Few things catch the eye like the ...

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 ...