About the International Gem Society (IGS)
…Come join our community! About the Founder Posing with some Quartz Donald Clark, CSM founded the International Gem Society in 1998. Donald…
…Come join our community! About the Founder Posing with some Quartz Donald Clark, CSM founded the International Gem Society in 1998. Donald…
Donald Clark, CSM, posing with some Quartz The International Gem Society (“IGS”) was founded by Donald Clark, CSM with the mission…
…cutting. “5 Star Gem,” Five-Pointed Star-Cut Variation, 81 Facets, 64 Index, by Donald Clark, CSM IMG Pavilion Step Angle Index…
…provide an affordable education in gemology. IGS’s founder — Donald Clark, CSM IMG — created a robust testing process…
…may be colored by impurities such as goethite (brown). Comments by Don Clark, CSM IMG Feldspars are our most common mineral, making up over 99%…
…of invisible inclusions that leave them a bit less than fully transparent. Donald Clark, CSM IMG A Follow-Up Question Thanks for the information.…
…from information provided by Donald Clark, CSM IMG, Dr. Gerald Wykoff, Dr. Clive Washington, Roy Kersey, and others. Vegetable Oil Variations…
…end, and just give it a gentle swing into contact. You get great control this way. Happy faceting, Donald Clark, CSM IMG “Faceting Machine…
…with polishing gemstones can take the fun out of faceting. I’ve been there! Best wishes, Donald Clark, CSM IMG “Gemstone Polishing…
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