Fluorescence Produced by Optical Defects in Diamond
How variations in UV lamp output can affect observed fluorescence color and intensity.
Nephrite Jade from Val Malenco, Italy: Review and Update
Analysis of 21 rough and gem-quality samples offers an update on the composition and properties of this pale green gem from the Italian Alps.
ダイヤモンド中の光学的欠陥：早見表 (英語)
A simple chart on optical defects in diamond, including those that produce coloration and fluorescence colors.
Optimizing Face-Up Appearance in Colored Gemstone Faceting
How contrast patterns can increase perceived brightness and optimize a gemstone's appearance.
Orangy Pink Coated "Soft Coral"
A coral specimen that was coated—not dyed—with a coloring agent only on the surface, an unusual method evidenced by microscopic features.
Rare Faceted Neptunite
Raman spectroscopy reveals orangy red neptunite in identification of a 11.78 ct faceted “black” octagonal modified step-cut stone.
ファンシーイエロー・ケープダイヤモンドの中に魚のような内包物を発見 (英語)
A recent lab examination at GIA New York revealed an inclusion in a rectangular Fancy Yellow called "pareidolia," which means it was a resemblance of the scales and form of a fish.
Turquoise-Rock Crystal Composite
Examination of a faceted rock crystal backed by a slice of turquoise—an obvious but unusual combination of gem materials.
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