Jonathan Tack Joins GSI as
Executive Vice President of Business Development

Jonathan Tack Joins GSI as Executive Vice President of Business Development

Jan 10, 2022 (New York, NY): Gemological Science International (GSI), one of the largest gemological organizations in the world and a global leader in diamond and jewelry certification, announced today that Jonathan Tack will join the organization as Executive Vice President of Business Development.

“I am thrilled to welcome Jonathan Tack to GSI,” says Debbie Azar, President and Co-Founder of GSI. “Our team is made up of leaders from the diamond and jewelry industry, and I am confident that Jonathan’s enthusiasm, energy, and vast industry knowledge will help GSI achieve continued growth and success.”

Jonathan has over 25 years of experience in the luxury goods sector. Following a decade of service as Vice President of Sales for Suberi Brothers where he revamped the legacy brand and launched e-commerce, Tack then founded Proposition Love where he designed for Cher, Kathy Griffin, and Tori Spelling and even appeared on the Chelsea Handler Show. Later, he led sales and marketing at Beauty Gem and SDC Designs. Throughout his career, Jonathan has successfully guided cross-functional teams while launching products into new markets, developing business strategies for multi-channel sales, and fostering lucrative partnerships. His professional drive and loyal relationships have brought him great success which he plans to continue at GSI.

“I am delighted to join such an esteemed and prestigious global organization,” says Jonathan Tack, Executive Vice President of Business Development, GSI. “The GSI team is building consumer trust and confidence in our industry through its integrity and innovation. I look forward to creating new opportunities that will be beneficial for GSI and for the entire diamond and fine jewelry industry.”

GSI is a globally renowned gemological organization that offers a myriad of services to the diamond and jewelry industry including grading reports and services for diamonds (both natural and lab-grown), colored gemstones, and jewelry. GSI is the leader in the testing and detection of undisclosed lab-grown diamonds in finished jewelry. The company also offers a variety of educational programs to the trade and has a dedicated internationally recognized team of researchers, scientists, and professionals committed to advancing gemological research in the industry.

For more information, please visit or to schedule an interview, please contact Duvall O’Steen of Luxury Brand Group (