Though still beautiful, melo pearls with color banding, like this specimen, are less valuable. Photo by Hienpq. Public Domain.

Calcareous Concretions - Natural, Rough, Orange - International Gem Society

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Calcareous Concretions – Natural, Rough, Orange

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Calcareous Concretions

Though still beautiful, melo <a href="https://www.gemsociety.org/article/pearl-jewelry-and-gemstone-information/" data-wpel-link="internal">pearls</a> with color banding, like this specimen, are less valuable. <a href="https://commons.wikimedia.org/wiki/File:Ngoc_oc.jpg" data-wpel-link="external" target="_blank" rel="external noopener nofollow">Photo</a> by <a class="extiw" title="vi:User:Hienpq" href="https://vi.wikipedia.org/wiki/User:Hienpq" data-wpel-link="external" target="_blank" rel="external noopener nofollow">Hienpq</a>. Public Domain.

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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;

Donald Clark, CSM IMG

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Dr. Joel E. Arem has more than 60 years of experience in the world of gems and minerals. After obtaining his Ph.D. in Mineralogy from Harvard University, he has published numerous books that are still among the most widely used references and guidebooks on crystals, gems and minerals in the world.
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Joel E. Arem, Ph.D., FGA

Fatma Oya Borahan, GG, FGG has Graduate Gemologist and Diamond Diplomas from the Gemological Institute of America (GIA) the German Gemmological Association (DGemG) and Gemmological Association of Great Britain (GemA). <a href="http://birdamlasu.com/">birdamlasu.com</a>

Fatma Oya Borahan, GG, FGG

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Barbara Smigel, PhD. GG

Dr. Gerald Wykoff is GG (Graduate Gemologist), a CSM (Certified Supreme Master gemcutter), educator, and author of several gemology books. He founded the American Society of Gemcutters in the 1980s and served for more than 10 years as the editor of its monthly magazine, American Gemcutter.

Dr. Gerald Wykoff GG CSM

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>.

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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.

Kyrylo Gubariev, Graduate Gemologist (GG, AJP)

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	Calcareous Concretions
Natural or man made	Natural
Gem State	Rough
Color	Orange
Transparency	Opaque