In Memory of Helene Fortunoff

CARLSBAD, Calif. – Nov. 9, 2021 – The GIA community – more than 3,300 associates around the world and hundreds of thousands of graduates – offers their condolences to the family of industry icon Helene Fortunoff, who passed away earlier this week.

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GIA Statement on Fraudulent Diamond Grading Reports in India

CARLSBAD, Calif. – Sept. 13, 2021 – In mid-August, as reported in the media, police in Surat, India, uncovered a fraudulent scheme involving counterfeit inscriptions linking lower-quality diamonds to GIA diamond grading reports for higher-quality stones.

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Measurement and Characterization of the Effects of Blue Fluorescence on Diamond Appearance

Using customized, image-based measurement systems to quantify the effect of fluorescence on the color, brightness, and transparency of gem diamonds viewed in both face-up and table-down orientations.

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Effects of Blue Fluorescence on Diamond Appearance, Color Treatment and Brightening of “Edison” Pearls, and a Pioneering Gemstone Market in Pakistan

An overview of the Summer 2021 Gems & Gemology content.

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Namak Mandi: A Pioneering Gemstone Market in Pakistan

Documents Namak Mandi’s transformation from a salt market to one of Pakistan’s primary gem trading centers, with a look at the commercial activities taking place today.

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Mobile Inclusions in a Decorative Quartz Object

Inspired fashioning showcases mobile inclusions in a polished quartz specimen, reminiscent of an hourglass.

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Iridescent Abalone Shell

The optical phenomenon of iridescence creates a beautiful pearly rainbow effect in an abalone shell.

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Colorful Inclusions in Diamond

Inclusions can be found in a variety of different gemstones; they create a window that allows the viewer to picture a stone’s formation history.

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Neptunite Inclusion in Benitoite

Raman analysis confirms that the yellow-orange to deep red inclusion in a faceted benitoite is indeed neptunite.

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CVD Laboratory-Grown Diamond with Counterfeit GIA Inscription

A CVD laboratory-grown diamond with a fraudulent GIA inscription is submitted to the Antwerp lab.

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Exquisite Opal Strand

Natural opal beads displaying vibrant play-of-color are strung together to create a remarkable necklace.

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Melo Pearl Found in a Melo Shell

A beautiful melo pearl is accidentally served up for lunch within its host gastropod.

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Transparent Rhodonite with Clarity Enhancement

A clarity-enhanced rhodonite stuns with its exceptional size, transparency, and vivid color.

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Rare Mixed Type IaB-IIb Diamond with a Long-Lasting Phosphorescence

Phosphorescent-based screening initially results in a rare mixed-type natural diamond falsely testing as laboratory-grown.

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Detection of Color Treatment and Optical Brightening in Chinese Freshwater “Edison” Pearls

Analyzes a group of 23 freshwater “Edison” pearls (a trade name referring to near-round freshwater cultured pearls, usually shell bead cultured) using various gemological and advanced instrumental techniques.

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Pearl Classification: The GIA 7 Pearl Value Factors

Provides a visual guide to GIA’s approach to classifying and describing pearls.

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Natural Freshwater Pearls from Europe: Russia, Scotland, and Germany

Analysis of eight European freshwater pearls of known provenance gives pearl specialists the opportunity to add greatly to GIA’s identification database.

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Bent Rutile in Rock Crystal Quartz

The authors recently examined a polished quartz disk with an unusual rutile (TiO2) inclusion.

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Quarterly Crystal: Heavily Etched Blue Beryl Crystals Reportedly from Pakistan

In previous Micro-World columns, the Quarterly Crystal entry has showcased exceptional crystalline specimens masterfully crafted by geological forces.

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Xenomorphic Olivine Inclusion in Diamond

A most unusually-shaped olivine inclusion in a faceted diamond takes a three-spoke form.

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