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Spinel

The Black Prince’s Ruby. The Timur Ruby. For centuries, spinel, the great imposter, masqueraded as ruby in Europe’s crown jewels.

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Stunning Color

The finest red spinel colors are pure red to slightly purplish red hues of medium to medium-dark tone.

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Cut for Brilliance

Spinel is most often cut in cushion and oval shapes; when properly proportioned it has excellent brilliance.

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Chromium

Like ruby, the color of red spinel is due to traces of chromium.

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Nature’s Perfection

Spinel belongs to the cubic crystal system and its characteristic crystal shape is an octahedron, which looks like two back-to-back pyramids.

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Perfect for Jewelry

Like ruby, spinel is found in alluvial deposits; it ranks 8 on the Mohs scale and has good toughness, making it a durable gem for jewelry.

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Collector’s Favorite

Well-formed spinel crystals are in high demand among mineral collectors.

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Tools

Research

A yellowish green glass with numerous wollastonite needles similar in appearance to the horsetail inclusions in demantoids.
Wollastonite in Devitrified Glass Imitating Horsetail Inclusions in Demantoid Garnet

A yellowish green specimen with horsetail-like inclusions is found to be glass rather than demantoid garnet.

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Three-Sided Phantom in Quartz
Quarterly Crystal: Wurtzite Phantom in Quartz

For the first time, wurtzite is found as an inclusion in gem material.

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Six-rayed star in an untreated spinel.
Star Spinel with Four and Six Rays

A cabochon displaying asterism is found to be an untreated spinel with two different stars.

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Colored stone pendants designed by Erica Courtney
Designs from Erica Courtney

Award-winning jewelry designer Erica Courtney presents four of her creations.

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Tsavorite garnet and red spinel from Miriam Kamau’s mining operation in Kenya
Interview with a Kenyan Miner and Dealer

Miriam Kamau relates how she became a prominent dealer and miner.

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The Geometeer, a synthetic ruby with a hybrid cut by Rex Guo.
Rex Guo: The Science and Art of Recutting Fine Gemstones

Rex Guo describes how he sources and systematically recuts faceted stones to unlock their inner beauty.

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Small unheated spinel and sapphire exhibited by Madagascar Imports
Unheated and Unusual Colors

Margit Thorndal of Madagascar Imports offers her perspective on the colored stone market.

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The gems spell out “The 2000th Gem Stone Design.”
Article
Gemstone ‘Paintings’ Tell Story of a Master Craftsman, Gem and Jewelry Mentor

A jeweler who quietly built a circle of inspiration and influence lives on in generations of GIA-educated jewelers and gemologists.

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Starlet in sunglasses above title “Hooray for Hollywood
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M.D. Hohenstine’s Gem Displays: The Process of Creating Popular Window Art with Loose Gemstones

Jeweler M.D. Hohenstine’s spectacular window displays were a beloved tradition in downtown Columbus, Ohio, for more than 50 years.

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Diaz needs to crouch low as he makes his way through jungle terrain with a backpack on. He wears boots and gloves to protect him on the uncut path.
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30-Year Marine Corps Veteran Fulfills Dream of Becoming a Field Gemologist

The rigors and often-harrowing conditions of gemology field expeditions are no match for 30-year Marine veteran with a love of gems.

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