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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

Two people walk past a Kay Jewelers storefront.
Article
Jewelry Sales Show Modest Rise; Higher End Soars

U.S. holiday jewelry sales increased slightly from 2018. Online buying surged, while foot traffic in retail stores slowed.

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Patrick O’Shea stands in front of a staircase at the Javits Center in New York City.
Article
The Curious Life of Patrick O’Shea: From Ballistics Detective to Gemologist and Jewelry Designer

Patrick O’Shea’s life’s journey has led him down many career paths until they all came together as a designer who specializes in masonic jewelry.

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A multi-diamond brooch.
Article
2019 in Review: Diamond Trade Begins Recovery, Jewelry Retail Blooms Late, Extraordinary Auction Sales

2019: A year of ups and downs in the gem and jewelry industry, including diamonds, retail, auction sales and laboratory-grown diamonds.

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A face-up view of a cushion cut diamond with blue color.
Article
Gems & Gemology’s 7 Most Unusual Encounters from 2019

Check out some of the most interesting and unusual diamonds and colored stones submitted to GIA’s laboratories in 2019.

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Bo Welu ruby and sapphires set in rings
Mineral Inclusions in Ruby and Sapphire from the Bo Welu Gem Deposit in Chanthaburi, Thailand

Spectroscopic and chemical analyses of emeralds from this Chinese deposit show a unique composition.

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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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