Windmills in Rare Mineral Sphalerite

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

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Fluorophlogopite in Burmese Spinel

Lotus Gemology in Bangkok received a large parcel of dark red spinels for identification.

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A Sapphire with a Negative Crystal Containing a Mobile Graphite Daughter Crystal

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

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Böhmite in Corundum

Rubies from Mozambique, which were examined at the Lotus Gemology lab in Bangkok, proved to be infilled with böhmite, a secondary mineral in corundum.

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Separation of Natural from Laboratory-Grown Diamond Using Time-Gated Luminescence Imaging

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.

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Optical Whitening and Brightening of Pearls: A Fluorescence Spectroscopy Study

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

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Naturally Colored Yellow and Orange Gem Diamonds: The Nitrogen Factor

Presents the four major groups of defects responsible for the color in nearly all yellow and orange diamonds.

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History of the Chivor Emerald Mine, Part II (1924–1970): Between Insolvency and Viability

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

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Quench-Crackled Dyed Blue Chalcedony Resembling Larimar

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

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Multiple Radiation Stains Suggest Interesting Geological Residency

A rough diamond crystal weighing 4.05 ct was observed with radiation staining on its surface.

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Hydrogen and Oxygen Stable Isotope Ratios of Dolomite-Related Nephrite: Relevance for Its Geographic Origin and Geological Significance

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

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Fossil Ivory Update with Lee Downey

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.

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Marble Imitation of Jadeite Rough

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

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Finders, Keepers: Field Trip to Crater of Diamonds, USA

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.

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The “Fragility of the Eternal” Kunzite: Origin, Cutting, and Identification

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

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Occurrence of Petrified Woods in the Russian Far East: Gemology and Origin

Scientists in Russia construct an origin story through the analysis of petrified wood popularly used in the souvenir trade.

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Greenish Blue Glass Imitating Gem Silica

Gem silica, also known as “chrysocolla chalcedony,” is considered the most valuable variety of chalcedony.

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Purplish Pink Diaspore Reportedly from Afghanistan

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.

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GIA 推出更详细的实验室制造钻石证书

加利福尼亚州卡尔斯巴德– 10 月 13 日 — 随着消费者对实验室制造钻石越来越感兴趣,GIA(美国宝石研究院)进一步提升其消费者保护使命,推出了 GIA 实验室制造钻石证书 (LGDR) — 包括适用于实验室制造钻石的四种新版数字证书(仅提供数字版),证书中包含 4C 颜色和净度规格。而以前,GIA 的实验室制造钻石证书使用的是描述性术语和等级范围。

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我如何才能知道自己的珠宝中镶嵌的花式米粒钻是不是天然钻石?

了解 GIA 如何解决业界所担忧的问题,即未经披露的实验室制造钻石和花式米粒钻仿品与天然花式米粒钻混在一起。

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