Assembled Bead Cultured Half-Pearl

Investigation in the Carlsbad laboratory reveals a pearl submission is not mabe as initially believed.

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Black Opal with Unique Play-of-Color

A black opal cabochon set in a ring displays vivid orange play-of-color.

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Green Jadeite-Omphacite from Guatemala

Bright green and nearly transparent jade from Guatemala, similar to jade from Myanmar, was available in Tucson.

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Dendritic Patterns in Emerald

A partially filled fissure in an emerald exhibits patterns resembling natural foliage.

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Fancy Vivid Yellow HPHT-Grown Diamonds

A report on a submission of 26 yellow HPHT-grown diamonds from the Hong Kong laboratory.

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Rose-Shaped Cloud Inclusion in Diamond

A cluster of cloud inclusions in diamond forms a petal-like structure resembling a rose.

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Large “Rainbow Calcite”

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“Hummingbird” in Orangy Yellow Diamond

An omphacite inclusion surrounded by fractures in an orangy yellow diamond takes the shape of a hummingbird.

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CVD Laboratory-Grown Gem Diamonds from Plasmability

A report from the New York laboratory on colorless and near-colorless CVD gem diamonds produced by the Texas-based company Plasmability.

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New Nigerian Green Beryl Find

Vendors in Tucson exhibited Nigerian green beryl with concentrated color zones.

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CVD-Grown Diamond with an Unusual Blue Band

An HPHT-treated CVD-grown diamond displaying a blue growth band is examined in the Mumbai laboratory.

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Copper in Indonesian Chalcedony

Examination of two chalcedony cabochons from a new source in Indonesia reveals an abundance of native copper.

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Tucson 2025 Overview

A summary of the findings at the 2025 Tucson gem shows.

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Aquamarine with Fluorite Inclusions

A large aquamarine crystal from Pakistan displays multiple eye-visible fluorite inclusions.

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Checkered Pattern on Diamond

The Mumbai laboratory examines a modified pear portrait-cut natural diamond.

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The 3309 cm^–1^ Series in Sapphire and Ruby: A Focus on FTIR Peak Position Variation

Investigates the correlations between peak positions in the 3309 cm–1 series with trace element concentrations for ruby, metamorphic and basalt-related blue sapphire, and laboratory-grown sapphire.

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Emeralds in Catherine de’ Medici’s Pendant: An Unexpected Geographic Origin

Archival research and gemological characterization reveal the geographic origin of two emeralds set in a pendant linked to Catherine de’ Medici, Queen of France from 1547 to 1559.

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A Study of the Winston Red: The Smithsonian’s New Fancy Red Diamond

Presents the first scientific and historical study conducted on the 2.33 ct Winston Red, the fifth-largest known Fancy red diamond in existence.

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“Enhydro” Amethyst from Morocco

A rare find of Moroccan amethyst with eye-visible fluid inclusions is spotted at the Pueblo show.

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Heated Corundum, the Remarkable Winston Red, and an Extraordinary Renaissance Jewel

An overview of the Spring 2025 Gems & Gemology content.

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