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Richard Nacken in 1907
Synthetic Emeralds Grown by Richard Nacken in the Mid-1920s: Properties, Growth Technique, and Historical Account

Describes the chemical, morphological, and microscopic properties of the first gem-quality synthetic emeralds ever produced, offering a historical perspective on their development.

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The 3543 CM-1 Infrared Absorption Band in Natural and Synthetic Amethyst and its Value in Identification

The proper use and limitations of IR spectroscopy for identifying natural versus synthetic amethyst of various types have been investigated, focusing on the region 3800–3000 cm-1.

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0.45 ct Pink CVD Labgrown Diamond
Strongly Colored Pink CVD Lab-Grown Diamonds

Pink CVD lab-grown products can be separated from natural and treated-color natural pink diamonds by a combination of gemological and spectroscopic properties, which are explored in this study.

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These two large synthetic diamonds were produced using HPHT growth methods by the Russian firm New Diamond Technology. The 4.30 ct specimen on the left has D color and SI1 clarity. On the right is a 5.11 ct sample with K color and I1 clarity. Photo by Wuyi Wang.
Article
Large HPHT-Grown Synthetic Diamonds Examined in GIA’s Hong Kong Laboratory

Examination of the largest HPHT synthetic diamonds GIA has examined so far demonstrated significant progress in this growth technology.

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2.51 and 3.23 ct CVD synthetic diamonds
Two Large CVD-Grown Synthetic Diamonds Tested by GIA

Two near-colorless rounds, weighing 3.23 and 2.51 ct, were the largest CVD-grown synthetic diamonds GIA has examined.

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Assortment of Linde synthetic star rubies and sapphires
Dual-Color Double Stars in Ruby, Sapphire, and Quartz: Cause and Historical Account

Examines a form of asterism comprising two six-rayed stars, one white and one that exhibits the stone’s bodycolor. Firsthand accounts and a survey of patent documents reveal that diffusion has been used to create or enhance this optical phenomenon in synthetic and possibly natural corundum since the 1950s.

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Skull memento mori locket ring
Article
Exhibition Review: Treasures and Talismans: Rings from the Griffin Collection

A review of Treasures and Talismans: Rings from the Griffin Collection at the Cloisters in New York.

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Gem Mountain mining site
Article
Update on Rock Creek Sapphire Deposit

An overview of recently expanded sapphire production at the Gem Mountain mine near Philipsburg, Montana.

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two large synthetic diamonds
Large HPHT-Grown Synthetic Diamonds Examined in GIA’s Hong Kong Laboratory

Examination of the largest HPHT synthetic diamonds GIA has examined so far demonstrated significant progress in this growth technology.

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Faceted CVD Synthetic Diamonds
CVD Synthetic Diamonds from Gemesis Corp

An examination of the gemological and spectroscopic properties of CVD synthetic diamonds from Gemesis Corp.

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