Evaluates a potential method of visually identifying HPHT-treated diamonds using microscopy to observe intense fluorescence at the facet edges and junctions.

An exploration of the distinction between jadeite and omphacite, plus GIA's current policy concerning the definition of these stones.

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Laboratory-Grown Diamond Seminar/Workshop

GIA’s industry-leading and globally-recognized diploma and certificate programs educate professionals with the skills needed for success in the gem and jewelry industry.

Synthetic overgrowth caused by two different types of treatment are found on two samples in the Tokyo lab.

A report from the 37th IGC, held in late October 2023 in Tokyo.

Large blue and pink diamonds were among the top lots of the fall auction season, including the most expensive auction jewel of 2023.

An unusual mite is preserved in a 30-million-year old amber specimen.

Dave Bindra shows some noteworthy pieces he obtained on the secondary market and shares his thoughts on the state of the colored stones market.

“Rainbow” andradite from Nara, Japan, occurs as relatively small orangy brown crystals that show attractive iridescence in almost the entire range of the spectrum.

The gem and jewelry industry mourns the loss of one of its true leaders.

Two flame-fusion synthetic sapphires with a Paraíba-like color are examined at GIA’s Carlsbad lab.

エドワード・ギュベリン博士が収集したコレクションの中には、世界各地から集められた珍しい宝石が数多く含まれている。

トルマリンは非常に複雑な化学組成を持ち、このグループには12種類以上の鉱物種が確認されている。

Edward Gübelin博士によって集められたコレクションの中には、世界中の産地からの珍しい宝石が多数あります。