The GIA Laboratory-Grown Diamond Report includes full quality assessment with a plotted clarity diagram. Color and clarity specification are described on the same scale as the GIA Diamond Grading ...

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 ...

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。

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, ...

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 ...

Citrine is one of the most popular yellow gems on the market. This designer cut shows off the warm glow of citrine’s sunny color. – Lydia Dyer, gem courtesy John Dyer & Co. Citrine—the transparent, ...

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 ...

サンストーンの珍しい変種はアベンチュレッセンスと呼ばれる独特なキラキラした輝きを示します。 銅 小さな銅の小片により、オレゴン産サンストーンに珍重される赤の色相が生じることがあります。 カラーゾーン サンストーンのなかには魅力的なカラー ...

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.

One of the most famous gems in the world, The Hope Diamond is a 45.52 carat Fancy Deep grayish blue diamond. GIA researchers examined it in 1988. Photo: Chip Clark, courtesy of Smithsonian Institution ...

as online features such as videos and slideshows. The history and mysteries behind a treasure of jewels hidden during the 1600s, a window to the past being fully opened to the public for the first ...

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 ...