Tourmaline
Tourmalines have a wide variety of exciting colors with one of the widest color ranges of any gem.


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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An overview of the geographic origin complexities facing the gem and jewelry industry today.
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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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Gem cutters - whether “gem whisperers” or mathematicians - create breathtakingly artistic individual gems and sculptures.
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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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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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Decent demand for finished jewelry, but less for loose gems. Plus: Lab-grown diamonds and responsible, sustainable business practices.
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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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Presents a simplified but comprehensive classification of gem tourmaline species based on quantitative measurement of six common major elements.
Read MoreCalculation Method for Tourmaline Species Classification Used Here
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