This 146.10-carat peridot is in the collection of the Natural History Museum in London Peridot has always been associated with light. In fact, the Egyptians called it the “gem of the sun.” Some ...

Zircon comes in a wide variety of colors. Colorless zircon is well known for its brilliance and flashes of multicolored light, called fire. These two zircon properties are close enough to the ...

Figure 1. These 20 completely non-nacreous pen pearls, from the group of 22 samples in this study, are set against a pen shell displaying both nacreous (left) and non-nacreous areas (right). Photo by ...

Renewed interest in large-scale commercial mining of Montana sapphires motivated a detailed study of the heat treatment of sapphire from the Rock Creek deposit. During the course of this systematic ...

CARLSBAD, Calif. – April 25, 2024 – Two leading gem and jewelry industry events will come together in September 2025, offering insight into cutting-edge gemological research, education, training and ...

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 ...

The cover of the newly published book, William Ruser: The Jeweler Who Charmed Hollywood, written GIA Research Librarian Judy Colbert and Co-Author Peggy Tsiamis. First book about the jeweler to the ...

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 ...

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 ...

GIAは、4月9日より、GIA ダイヤモンド ドシエ レポートの印刷版発行を再開することを決定いたしました。4月9日にGIAラボラトリーにあるすべてのダイヤモンド、または同日以降にダイヤモンド ...

The GIA App contains a wealth of diamond resources, including 4Cs interactive tools, and expert articles and videos. Additionally, within the GIA App you can access reports in GIA’s secure database ...

This 10.12 ct Fancy Vivid yellow pear shape illustrates the effect a fancy shape can have on intensifying the color in a yellow diamond. - Courtesy the Scarselli Family Color In diamonds, rarity ...