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A blue synthetic star sapphire from past production of Wiede’s Carbidwerk
Synthetic Star Sapphires and Rubies Produced by Wiede’s Carbidwerk, Freyung, Germany

Details the process used by Wiede’s Carbidwerk to produce star synthetic corundum from the mid-1950s until the 1970s.

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Drilled natural pearls examined in this study.
Saltwater Pearls from the Pre- to Early Columbian Era: A Gemmological and Radiocarbon Dating Study

Examines 85 saltwater natural pearls, reportedly harvested from the Caribbean islands off the coast of Venezuela during the early 16th century, to determine their age.

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10.08 ct HPHT synthetic diamond with color equivalent to Fancy Deep blue
Blue HPHT Synthetic Diamond Over 10 Carats

Results from GIA’s recent testing of a 10.08 ct blue HPHT synthetic diamond, the largest HPHT synthetic recorded to date.

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Samples of by-product synthetic zincite
Characteristics of Gem-Quality By-Product Synthetic Zincite

Investigates the properties of synthetic zincite produced by industrial kilns in Poland.

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Gem Mountain mining site
Update on the Rock Creek Sapphire Deposit

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

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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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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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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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Aquamarine necklace
Article
Exhibition Review: Maker & Muse, Women and Early 20th Century Art Jewelry

A review of the “Maker & Muse, Women and Early 20th Century Art Jewelry” exhibition at Chicago’s Driehaus Museum.

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Gem Mountain mining site
Article
Update on the Rock Creek Sapphire Deposit

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

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