The De Beers Cullinan Blue was the early buzz of the spring 2022 auction season, with the 15.10 ct Fancy Vivid blue step-cut diamond far surpassing Sotheby’s presale estimate of $48 million. Bringing ...
Figure 1. The sparsely populated high desert of eastern Oregon is home to three localities producing natural copper-bearing labradorite feldspar. In this view of Lake County’s Dust Devil mine, the ...
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 ...
Search a city or postal code to find retailers who carry GIA-graded diamonds or have GIA-trained staff. Results will include addresses, store hours and directions. Store hours reflected on Retailer ...
Figure 1. The color zoning of amethyst from Boudi often displays a characteristic hourglass shape. Photo by Abdelghani El Harfi and Salahaddine Mouaddib. For 25 years, the Moroccan locality of Boudi ...
The authors used Vis-NIR spectral measurements combined with LA-ICP-MS data to investigate the usefulness of absorption spectra for differentiating between copper and iron as sources of greenish blue ...
Figure 1. The GIA 7 Pearl Value Factors system classifies pearls according to size, shape, color, luster, surface, nacre, and matching. Composite photo by GIA staff. Prized by many cultures throughout ...
This large Australian light opal cabochon weighs 117.85 carats. Small play-of-color flashes of orange and green predominate in a pinfire pattern, with spots of a more muted blue over a grayish ...
Figure 1. The bright red faceted ruby in this gold ring is from the large and potentially productive Snezhnoe deposit in Tajikistan. Photo by Zamoniddin Z. Nasriddinov. Discovered during the late ...
Rough amber sometimes contains assorted plant and insect inclusions. Many are even visible without magnification. Amber is an organic gem. Organic gems are the products of living or once-living ...
View the holiday schedule for all GIA locations worldwide.
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 ...
Some results have been hidden because they may be inaccessible to you
Show inaccessible results