In this Ethiopian opal cut by AGTA Spectrum Award-winner Mark Kaufman, you can see the “brushstroke” appearance that characterizes the play of color of most natural opals. 13.23 cts, 2.4 x 1.5 x 0.8 cm. © Rob Lavinsky, www.iRocks.com. Used with permission.

Opal Stone | Yellow | 13.23 ct - International Gem Society

Opal Stone id-m-440748 - International Gem Society

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Opal Stone | Yellow | 13.23 ct

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Opal Stone

In this <a href="https://www.irocks.com/minerals/specimen/39460" data-wpel-link="external" target="_blank" rel="external nofollow">Ethiopian opal</a> cut by <a href="https://agta.org/spectrum/overview/awards-and-honors/" data-wpel-link="external" target="_blank" rel="external nofollow">AGTA Spectrum Award</a>-winner Mark Kaufman, you can see the "brushstroke" appearance that characterizes the play of color of most natural <a href="https://www.gemsociety.org/article/opal-jewelry-and-gemstone-information/" data-wpel-link="internal">opals</a>. 13.23 cts, 2.4 x 1.5 x 0.8 cm. © Rob Lavinsky, <a href="https://www.irocks.com/" data-wpel-link="external" target="_blank" rel="external nofollow">www.iRocks.com</a>. Used with permission.

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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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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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Jim Buday was born and raised in Wisconsin. He attended college for biology, but realized that he preferred to work with his hands. He became a general contractor and home flipper. Jim then taught himself to cut gems by watching instructional YouTube videos and reading online forums. By 2019, he was confident enough in his skills to pursue selling his work. He founded the Reddit thread, Shinypreciousgems, which now sits at more than 25,000 members. Jim now works with gems and jewelry full time, and has also partnered with several jewelers to offer settings to his gemstone clients. Recently, Jim started creating his own gem designs. In his free time, Jim enjoys the outdoors, working on his land, and is building a house with his girlfriend, Raeanna.

Gemstone	Opal Stone
Natural or man made	Natural
Origin	Ethiopia
Carat Weight	13.23
Height	24
Width	15
Depth	8
Gem State	Cabochon
Color	Yellow
Transparency	Translucent
Photo phenomena	Play of Color