Gemological Science International

Gemological Science International (GSI) is an independent gemological laboratory that provides professional gemstone identification, grading and appraisal services to the fine jewelry industry. It was founded by Mark Gershburg, former CEO of EGL USA and member of World Diamond Council (WDC), in March, 2005. GSI’s management team collectively offers over three decades of experience in the gem laboratory industry. GSI are located in the heart of New York City's Diamond District.

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GSI has re-engineered the processing paths for gem I.D. and grading, which has resulted in higher levels of productivity and reduced costs. These cost efficiencies are passed on to our customers and ultimately to consumers. This means that more consumers can afford the benefits of having a grading report for their gemstones, including low-cost items.’