This is one of two stones I cut from a single crystal.  The color on the "c" axis varied somewhat from one end of the crystal to the other, so the matched pair didn't quite match.  This is the darker of the two and has a notably richer color with more blue than the photo shows.  See item to311 for it's identically cut, but slightly lighter mate. Color: Medium Blue-Green, Cut: Emerald, Weight: 2.58, Dimensions: 6.9 x 9.4 mm. (Information supplied by photo contributor.) &copy; Daniel Stair, CustomGemstones.com

This is one of two stones I cut from a single crystal. The color on the &#8220;c&#8221; axis varied somewhat from one end of the crystal to the other, so the matched pair didn&#8217;t quite match. This is the darker of the two and has a notably richer color with more blue than the photo [&hellip;]

Tourmaline | Green | 2.58 ct

Tourmaline id-g-20456 - International Gem Society

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Tourmaline

This is one of two stones I cut from a single crystal. The color on the "c" axis varied somewhat from one end of the crystal to the other, so the matched pair didn't quite match. This is the darker of the two and has a notably richer color with more blue than the photo shows. See item to311 for it's identically cut, but slightly lighter mate. Color: Medium Blue-Green, Cut: Emerald, Weight: 2.58, Dimensions: 6.9 x 9.4 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.

Addison Rice

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>.

Jeff R. Graham

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.

Bear Williams

Cara Williams, FGA, is Vice-President and Senior Staff Gemologist at <a href="https://stonegrouplabs.com/">Stone Group Laboratories</a>. Cara is a fellow of the Gemmological Association of Great Britain (Gem-A). She has been a tutor for the prestigious Diploma in Gemmology course for the Gem-A in London for more than 15 years. Growing up in a retail jewelry family with a concentration in colored stones, Cara has been in the wholesale trade since 1986. She brings a lifetime of experience working with gems to the lab, her students, and many published articles.

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Kyrylo Gubariev, Graduate Gemologist (GG, AJP) is a gemologist with a passion for sharing his knowledge with fellow gem lovers. Originally from Ukraine, he is currently based in Bangkok, Thailand.

Gemstone	Tourmaline
Natural or man made	Natural
Origin	Afghanistan
Origin details	Afghanistan
Carat Weight	2.58
Gem State	Faceted
Faceter	Daniel Stair
Color	Green
Transparency	Transparent