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Diamond

Diamonds are among nature’s most precious and beautiful creations.

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Color

Colorless diamonds are scarce—most diamonds have tints of yellow or brown.

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4Cs

Factors used to describe diamonds: Clarity, Color, Cut, Carat Weight

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Rarity

The rarity of one or more of the 4Cs can affect value.

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Octahedron

The crystal shape of a gem diamond is often the octahedron.

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Trigons

Trigons—little triangular depressions—occur only on octahedral faces.

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Growth marks

Diamond’s growth marks help experts separate diamonds from simulants.

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Tools

Research

A truck travel the circular roadways of the large mine.
Article
US Consumer Confidence Remains Strong; Alluvial Diamond Tracking and Illegal Gold

U.S. consumer confidence has kept the economy from sliding into a possible recession. Plus: Sustainable trends for diamonds, gold.

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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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A pile of rough diamonds.
Article
US Government to Industry: Know Your Supply Chain; De Beers, Alrosa Cut Rough Sales

De Beers and Alrosa slashed rough diamond sales after ABN AMRO’s says it will no longer finance rough purchases for goods that can’t be cut profitably.

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Kimberlites: Earth’s Diamond Delivery System

Examines the basic characteristics of kimberlites and their relationship with diamonds.

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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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Scene of a retail street.
Article
Chow Tai Fook Expands Blockchain Initiative with GIA

Chow Tai Fook and GIA offer secure digital blockchain reports that document the diamond journey and grading information in one place.

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Six different shaped red and pink diamonds lined up in a row.
Article
Bank Suspends Credit for ‘Unprofitable’ Rough Diamonds

De Beers and Alrosa slashed rough diamond sales after ABN AMRO’s says it will no longer finance rough purchases for goods that can’t be cut profitably.

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Emerald and diamond brooch.
Article
Jewels of Hollywood: Accessories and Jewelry that Made the Stars Shine

“Jewels of Hollywood,” on loan from the Kazanjian Foundation, showcases some of the jewelry and accessories associated with Hollywood royalty.

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A ruby and diamond choker. The center section is made of six strands of red pearls, framed by rubies and diamonds.
Article
Mughal Jewels Auction: Al-Thani Collection Raises $109 Million

Collectors from around the world descended on Christies’ Maharajas & Mughal Magnificence auction of the jewels from the Al-Thani Collection on June 19.

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