Extremely nice color for a Nigerian green tourmaline.  This one shows flashes of slightly bluish green and yellowish green, with only a tiny bit of olive green showing on the long edges.  The cut is a modified brilliant oval with some extra facets on the bottom and a supernova crown design, so it is nice and lively compared to most other ovals. Color: Medium Green, Cut: Fancy Brilliant Oval, Weight: 5.51, Dimensions: 9.3 x 12.8 mm. (Information supplied by photo contributor.) &copy; Daniel Stair, CustomGemstones.com

Extremely nice color for a Nigerian green tourmaline. This one shows flashes of slightly bluish green and yellowish green, with only a tiny bit of olive green showing on the long edges. The cut is a modified brilliant oval with some extra facets on the bottom and a supernova crown design, so it is nice [&hellip;]

Tourmaline | Green | 5.51 ct

Tourmaline id-g-20893 - International Gem Society

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Tourmaline

Extremely nice color for a Nigerian green tourmaline. This one shows flashes of slightly bluish green and yellowish green, with only a tiny bit of olive green showing on the long edges. The cut is a modified brilliant oval with some extra facets on the bottom and a supernova crown design, so it is nice and lively compared to most other ovals. Color: Medium Green, Cut: Fancy Brilliant Oval, Weight: 5.51, Dimensions: 9.3 x 12.8 mm. (Information supplied by photo contributor.) <a href="http://customgemstones.com/" data-wpel-link="external" rel="nofollow external">© Daniel Stair, CustomGemstones.com</a>

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The late Donald Clark, CSM founded the International Gem Society in 1998. Donald started in the gem and jewelry industry in 1976. He received his formal gemology training from the Gemological Institute of America (GIA) and the American Society of Gemcutters (ASG). The letters &#8220;CSM&#8221; after his name stood for Certified Supreme Master Gemcutter, a designation of Wykoff&#8217;s ASG which has often been referred to as the doctorate of gem cutting. The American Society of Gemcutters only had 54 people reach this level. Along with dozens of articles for leading trade magazines, Donald authored the book &#8220;Modern Faceting, the Easy Way.&#8221;

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A geologist, environmental engineer and Caltech graduate, Addison&#8217;s interest in the mesmerizing and beautiful results of earth&#8217;s geological processes began in her elementary school&#8217;s environmental club. When she isn&#8217;t writing about gems and minerals, Addison spends winters studying ancient climates in Iceland and summers hiking the Colorado Rockies.

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The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as <a href="https://rockpeddler.com/product-category/instructional-materials/">Gram Faceting Designs</a>.

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Bear Williams, CG, FGA (Hon), is President and Laboratory Director at <a href="https://stonegrouplabs.com/">Stone Group Laboratories</a>. Bear travels to gem producing countries and treating regions researching the latest trends in gemology and visiting with other lab directors. On-site research allows him to keep abreast of new synthetics and treatments in the marketplace. He regularly meets with other gemological associations and labs, and together will present research findings, and discuss the latest nomenclature or laboratory issues relevant to the trade and consumers. Recognized as an expert in the field of digital spectroscopy, Bear operates UV-Vis-NIR, ED-XRF, FTIR, UV, and Raman Spectrometers.

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Gemstone	Tourmaline
Natural or man made	Natural
Origin	Nigeria
Origin details	Nigeria
Carat Weight	5.51
Gem State	Faceted
Faceter	Daniel Stair
Color	Green
Transparency	Transparent