Figure 1. Left: 18K yellow gold “Flames” ring with 25.19 ct Mexican fire opal. Right: This 18K yellow gold “Spice” ring ...

Industry-leading research, education and innovation have kept GIA on the cutting-edge of gemology since 1931, and we invite you to join us during JCK to experience our latest discoveries! Visit us in ...

A 1.09 ct D-color diamond grown by chemical vapor deposition (CVD) was recently submitted to the Mumbai laboratory. This submission displayed an interesting blue band, seen through the pavilion facets ...

Chemical vapor deposition (CVD) technology has been widely used to grow diamonds for the jewelry market, targeting popular colors and sizes. The majority of these products are colorless to ...

GIA’s Bangkok laboratory received for identification a set of 35 loose non-nacreous pearls displaying a wide range of bodycolors including white, orange, pink, brown, purple, and black. The pearls ...

The published literature offers only a few records of direct measurement of the natural radioactivity in nephrite. The present study used high-purity germanium (HPGe) low-background gamma-ray ...

Verifying the gold content of karat-gold jewelry is a problem for the entire industry. This study compares four widely available testing methods: density (measured by hydrostatic weighing), chemical ...

The 75.47-carat Hooker Emerald was worn by Ottoman Sultan Abdul Hamid II, the last sultan of the Ottoman Empire. Photo by Chip Clark, courtesy Smithsonian Institution, National Museum of Natural ...

この75.47カラットのHooker（フッカー）エメラルドは、オスマン帝国最後のスルタンであったアブドゥル·ハミド2世が着用したもの。 - Chip Clark、提供：Smithsonian Institution, National Museum of Natural ...

Attain your dream of a GIA education with the help of a scholarship, grant, or loan. GIA also accepts outside sources to fund your education, including vocational rehabilitation and Veterans’ benefits ...

This course covers how to describe diamond jewelry accurately for effective and ethical sales conversations with customers. Key topics examined include the internationally accepted GIA clarity grading ...

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 ...