Natural-Color D-to-Z Diamonds: A Crystal-Clear Perspective

Examines a very large dataset of colorless to near-colorless diamonds submitted to GIA and evaluates their diamond type and spectroscopic properties.

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Magnetite Inclusions in Star Peridot

Magnetite inclusions in a four-rayed star peridot help to date its terrestrial age.

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Quarterly Crystal: Ferrocolumbite in Topaz

“Star cruisers” formed of ferrocolumbite seem to fly in a large topaz crystal from the Shigar Valley in Pakistan.

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Unique Raindrop Pattern of Turquoise from Hubei, China

Presents spectroscopic and chemical analysis of a new variety of turquoise with a rare raindrop pattern with saturated colors.

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Synthetic Moissanite with Fraudulent GIA Inscription

GIA Johannesburg identifies fraudulent GIA inscriptions on several synthetic moissanites submitted as diamonds.

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Color-Change Cat’s-Eye Diaspore

A 60.71 ct cabochon was recently submitted to the Tokyo lab for identification.

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Vietnam: Shell Nuclei, Pearl Hatcheries, and Pearl Farming

Reports on a visit to a shell nucleus manufacturer and two pearl farms in northern Vietnam, which is emerging as a notable producer.

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A Near-Field-Communication (NFC) Technology Device Embedded in Bead Cultured Pearls

The Carlsbad laboratory received for examination two dark-colored bead cultured pearls embedded with an electronic device from Jeremy Shepherd, CEO of Pearl Paradise.

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Inclusion and Trace Element Characteristics of Emeralds from Swat Valley, Pakistan

Presents a detailed study of gemological properties, inclusion features, spectroscopic characteristics, and chemical composition of emeralds from this important source.

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A History of European Royal Jewel Sales, Including Sotheby’s 2018 Auction of Marie Antoinette’s Jewels

Chronicles important auctions of jewels from European royal collections over the years, with a focus on a recent high-profile sale of items that once belonged to Marie Antoinette.

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蛤蜊浓汤配珍珠

近日,GIA 纽约鉴定所有幸检验了一颗迷人的珍珠,它的故事更加引人入胜,快来一探究竟吧。

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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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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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Fluorophlogopite in Burmese Spinel

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

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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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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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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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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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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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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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