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LCM reveals traces of catalyst and step-like growth marks.
Observation of Etched Surface Micro-Features on HPHT Synthetic Diamonds Using Laser Confocal Microscopy

Laser confocal microscopy, a very reliable method of revealing surface micro-features, is used on an HPHT synthetic diamond to reveal growth structures.

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The wax-impregnated bangle (left) showed bluish fluorescence under long-wave UV.
Strong Fluorescence in B-Jade Impregnated with Wax

A bangle is an example of the misconception that B jade is only impregnated by resin, when in fact wax-impregnated jadeite is also considered B-jade.

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A green-blue specimen was identified as Maxixe-type beryl.
Green-Blue Maxixe-Type Beryl

A transparent greenish-blue pear-shaped gemstone, reportedly from Madagascar, is discovered to be a Maxixe-type beryl.

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A black star sapphire with one set of golden rays and another set of silver rays.
Twelve-Rayed Star Sapphire from Thailand

A black star sapphire produced from eastern Thailand, showing both golden and silver rays, is studied at GIA’s Bangkok lab.

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Barbara Palumbo, Monica Stephenson, and Sarah Yood speak at the conference.
IAC Conference on Responsible Gold

A report from the eighth annual International Gold Conference, held in New York on 12-13 April 2018.

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A miner in northern Tanzania examines rhodolite.
Gemstone Guidebook Project

A project coordinated by GIA and the NGO Pact provides a valuable educational tool to women miners in Tanzania.

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Two white jade bracelets with dark color patches.
Nephrite Bracelet with Filled Cavity

A jade bracelet contains unusual fillers, used to create a smooth surface.

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These rubies were determined to be glass filled, partly due to the use of the DiamondView.
Separating Glass-Filled Rubies Using the DiamondView

The DiamondView instrument is able to identify glass as the filler in a pair of heart-shaped rubies.

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Walstromite inclusion with fan-shaped black fractures.
D-Colour Natural IIa Diamond with Walstromite Inclusion

A diamond is proven to have a superdeep origin through an inclusion of CaSiO3-walstromite.

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Garnets under daylight-equivalent (left) and incandescent light (right).
Discovery of Colour-Change Chrome Grossular Garnets from Ethiopia

The first known group of colour-change gem-quality chrome grossular garnet, reportedly from Ethiopia, is examined in GIA’s Carlsbad lab.

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