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Sapphire

The name “sapphire” can also apply to any corundum that’s not ruby red, another corundum variety.

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Madagascar Beauty

This 7.04-ct. oval sapphire is from a new source, the island Madagascar.

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Blue Velvet

Deep, intense, velvety blue describes this sapphire’s color.

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Best in Daylight

Blue sapphire looks best in daylight and fluorescent light.

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Spindle Shape

This spindle-shaped crystal from Sri Lanka weighs 70.10-cts.

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Color Zoning

Blue color distribution in sapphire crystals is often uneven.

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Twinned

There is a second sapphire crystal growing into the larger one.

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Tools

Research

A diamond necklace that features a 100.02 Fancy Intense yellow diamond. The pendant is done in the shape of a musical instrument.
Article
Bullish Predictions for 2019 Holiday Sales Despite Concerns, Sotheby’s Hong Kong Auction Sales

U.S. holiday sales predictions are better than expected. Sotheby’s Hong Kong auction features a 100 ct yellow diamond necklace by GIA alumna Anna Hu.

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A large group of people outside on GIA’s Carlsbad, California  campus.
Article
Guardians of Trust: GIA’s Innovative Research, Instruments and Services

GIA’s services and instruments have grown in importance and impact as new gem treatments and laboratory-grown gems enter the market.

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Sapphires from Madagascar
Madagascar Sapphire: Low-Temperature Heat Treatment Experiments

Shows how the color of Madagascar sapphire is lightened with heating to relatively low temperatures below 1350°C.

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Man sits at his desk with a display stand of multiple pieces of jewelry in front of him.
Article
Alum’s Lifelong Quest: Searching for Jewelry Unicorns

Alan Nacht continues his family’s legacy - Bernard Nacht & Co. – and his quest for unforgettable jewelry.

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The octopus head is a baroque Tahitian cultured pearl and its arms are made of black, yellow and white diamond (in a striped pattern) set in black-plated 18K gold.
Article
A Tropical Paradise of Ocean-Inspired Jewelry and Gemstones

Escape to a warm-water paradise in your mind with these jewels that formed in the sea, are inspired by marine life and evoke the ocean’s essence.

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Looking down the crystal axis of a backlit 58.83 ct trapiche emerald
Article
Emerald: The Superstar of Trapiche Gemstones

Trapiche emeralds, which display a distinct six-spoke wheel pattern, set the standard as some of the finest and most spectacular crystals unearthed.

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Inclusions in sapphire SASLR050_01.
U-Pb Ages of Zircon Inclusions in Sapphires from Ratnapura and Balangoda (Sri Lanka) and Implications for Geographic Origin

Establishes a metamorphic origin for sapphire samples from these deposits, supported by their trace-element composition and inclusion characterization, including the age dating of zircon inclusions.

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Details of two engravings representing the treasury of Aachen Cathedral.
The Talisman of Charlemagne: New Historical and Gemological Discoveries

Reveals new details about this historical jewel and the results of its first gemological analysis.

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GIA field expedition team in Ethiopia
Land of Origins: A Gemological Expedition to Ethiopia

Documents a visit to the sapphire, opal, and emerald mining and trading areas of Ethiopia.

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A group of rough sapphires encircle cut sapphires.
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Montana Yogo Sapphires’ Unique Gemology

A look at the mining and distinguishing characteristics of this naturally vibrant blue sapphire.

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