Examines the effectiveness of hydrogen and oxygen isotopes in discriminating dolomite-related nephrites from the four most important occurrences worldwide.

Presents a study that suggests optically brightened pearls can be consistently separated from non-brightened pearls using fluorescence spectroscopy.

Mineral and fluid phases within negative crystals in metamorphic sapphires provide us with general information on the sapphire and the trapped fluid itself.

Researchers from De Beers Group Technology present a technique that expands on the surface luminescence used in the DiamondView instrument to provide additional imaging information and quickly distinguish colorless or near-colorless natural diamond from laboratory-grown diamond.

A master gem carver bases his latest design off a stunning stained glass window when attempting the world’s largest known cut kunzite.

Whimsical windmill-like inclusions are found in a high-quality orange specimen of the rare mineral sphalerite.

Diaspore, an orthorhombic aluminum oxide hydroxide mineral with the formula AlO(OH), is a relative newcomer to the jewelry scene, with some stones possessing a captivating ability to change color between pale green, yellow, pink, and purple when viewed in different sources of light.

Many legends are told about the history of the Chivor emerald mine.

There’s only one place on earth where the general public can prospect for diamonds directly from a primary kimberlite pipe: Crater of Diamonds State Park.

Lee Downey, owner of Artifactual (Tucson, Arizona), spoke with us in early 2020 about his 35 years in the fossil ivory carving trade and the impact of ivory bans on his business.

Raman spectroscopy confirms sea-blue beads with a similar appearance to Larimar are actually quench-crackled chalcedony.

In recent decades, jadeite prices have risen dramatically. Driven by profit, a variety of imitations are found in the jadeite jewelry market.

非開示のラボラトリー グロウンおよび類似石のファンシー メレーが天然ファンシー メレーに混在していることに対する業界の懸念にGIAがどのように対処しているかについて学びましょう。

Webinars are an easy, informal way for GIA experts to share information and stay connected to the community of researchers and gem and jewelry lovers.

宝石学フォトジャーナリストのRobert Weldonが、お気に入りの写真に秘められた逸話を紹介します。

Presents a quantitative means of determining the causes of color in a gem material, using corundum’s six major chromophores as an illustration.

A transparent supply chain and the education of artisanal miners were two of the many topics discussed at Tucson’s first Ethical Gem Fair.

A ring made entirely of natural diamond was recently submitted to GIA’s New York laboratory.

Violent kimberlite eruptions impact the surface features of diamonds, which can give scientists useful information about how diamonds react with the fluids in the mantle.

A rare Burmese star peridot cabochon is characterized by a soft four-rayed asterism and extremely fine acicular inclusions.