Our mission is to make gemology accessible and affordable


Established in 1998, IGS is the largest online gemology resource and community.

Who are IGS members?

A society is about people that are interconnected. Here at IGS, our passion for gemstones brings us together. IGS has members on every continent (except Antarctica) who range from seasoned professionals to the merely curious.

What people are saying

  • I very much liked the Diamond Specialist Course, it is excellent, as comprehensive as it could be, and its structure offers all the theoretical and practical knowledge for grading and evaluating diamonds. Moreover, IGS related articles complement and consolidate what you learned during the course. "
    Daniel PenescuIGS Member
  • I have been faceting gems as a hobby and just wanted to learn more about what I was really doing. I have gotten hooked now and really enjoyed your course. It is very well done . I'm going to see where this may lead me in the future now. Thank you all so much! "
    James MullinIGS Member
  • I have never known or heard of an organization that offers so much for its members, and at such a low cost. What started as a hobby in 1998 and now is a small home business for my wife and I has been made so much easier by the information you supply. Thank you. "
    Ernest and Peggy Roisch, Rainbow Rocks, LTD IGS Member
  • You know the best thing that I have learnt from your great courses is that it does not matter how much you think you know about gems, you never stop learning, each day there is something more learn, it will never stop. Thank all for the help, education and support that you give IGS members. "
    Peter CheckleyIGS Member

    The IGS Team

    The management and advisory team at IGS is a diverse group of professionals committed to delivering our mission.

    Seth and Lisa Rosen

    Seth and Lisa Rosen

    Company Management

    In 2012, Donald Clark retired and passed along stewardship of the IGS to Seth and Lisa Rosen. Seth and Lisa were longtime members of the IGS. Seth is a gem collector and active Internet entrepreneur, who had already spent a great deal of time in the custom jewelry business. He...
    Meet Seth and Lisa Rosen
    Donald Clark, CSM

    Donald Clark, CSM IMG

    Founder

    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 "CSM" after his name stood for...
    Meet Donald Clark, CSM IMG

    Jeffery Bergman, SSEF SGC

    Vice President Emeritus

    Jeffery Bergman, SSEF SGC, founder and director of 8th Dimension Gems in Thailand, is an American gem dealer with more than 40 years of experience in gemstone and fine jewelry mining, cutting, wholesaling and retailing. His career has taken him to more than 50 countries and every continent except Antarctica....
    Meet Jeffery Bergman, SSEF SGC

    Joel E. Arem, Ph.D., FGA

    Contributor

    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...
    Meet Joel E. Arem, Ph.D., FGA

    Fatma Oya Borahan, GG, FGG

    Contributor

    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). birdamlasu.com
    Meet Fatma Oya Borahan, GG, FGG

    Barbara Smigel, PhD. GG

    Contributor

    Barbara Smigel is a GIA certified gemologist, facetor, jewelry designer, gem dealer, gemology instructor and creator of the well-regarded educational websites acstones.com and bwsmigel.info.
    Meet Barbara Smigel, PhD. GG

    Dr. Gerald Wykoff GG CSM

    Contributor

    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.
    Meet Dr. Gerald Wykoff GG CSM

    Addison Rice

    Staff Writer

    A geologist, environmental engineer and Caltech graduate, Addison's interest in the mesmerizing and beautiful results of earth's geological processes began in her elementary school's environmental club. When she isn't writing about gems and minerals, Addison spends winters studying ancient climates in Iceland and summers hiking the Colorado Rockies.
    Meet Addison Rice

    Jeff R. Graham

    Contributor

    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 Gram Faceting Designs.
    Meet Jeff R. Graham

    Bear Williams

    Contributor

    Bear Williams, CG, FGA (Hon), is President and Laboratory Director at Stone Group Laboratories. 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....
    Meet Bear Williams

    Cara Williams

    Contributor

    Cara Williams, FGA, is Vice-President and Senior Staff Gemologist at Stone Group Laboratories. 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...
    Meet Cara Williams

    Kyrylo Gubariev, Graduate Gemologist (GG, AJP)

    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.
    Meet Kyrylo Gubariev, Graduate Gemologist (GG, AJP)

    Never Stop Learning

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