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Tourmaline
Tourmalines have a wide variety of exciting colors with one of the widest color ranges of any gem.
Tools
Geographic Origin Determination of Paraíba Tourmaline
Copper-bearing gem tourmaline, known as Paraíba tourmaline after the location of its original discovery, is prized for its vivid blue to green color. This article explains GIA’s use of quantitative chemical analyses to distinguish samples from Brazil, Nigeria, and Mozambique.
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The Geographic Origin Dilemma
An overview of the geographic origin complexities facing the gem and jewelry industry today.
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Field Gemology: Building a Research Collection and Understanding the Development of Gem Deposits
With more than 90 field expeditions on six continents since 2008, GIA has accumulated over 22,000 colored stone reference samples. This extensive collection of colored stones with known origins supports GIA’s research on geographic origin determination.
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Article
Making the Cut: The Art and Science of Fantasy Carving
Gem cutters - whether “gem whisperers” or mathematicians - create breathtakingly artistic individual gems and sculptures.
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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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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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Article
Headwinds Slow 2019 Vegas Business, Lab-grown Diamonds Proliferate
Decent demand for finished jewelry, but less for loose gems. Plus: Lab-grown diamonds and responsible, sustainable business practices.
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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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A New Method for Determining Gem Tourmaline Species by LA-ICP-MS
Presents a simplified but comprehensive classification of gem tourmaline species based on quantitative measurement of six common major elements.
Read MoreAppendix 3: Calculation Method for Tourmaline Species Classification Used Here
Calculation Method for Tourmaline Species Classification Used Here
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