What Does GSI Certified Mean?

A GSI certified stone is one that consumers can trust.

What does GSI certificated mean? How are stones that are GSI certificate graded? What is the difference between  GSI certified vs. GIA certified?

If these are your questions, this age can help to answer them.



Gemological Science International (GSI) is an independent commercial gemological laboratory. We combine state-of-the-art technology with deep professional expertise.

GSI provides reliable, fast, and professional gemstone identification as well as grading and appraisal services to the global fine jewelry industry. GSI is the only major gemological laboratory established in the 21st century. Within a relatively short period of time, GSI has grown to become one of the largest gem labs in the world.

In recent years, GSI has expanded its global footprint by opening offices in the United States, India, Israel, Belgium and Botswana. From New York City to Antwerp and Mumbai, GSI works in close proximity to our clients in jewelry manufacturing, fabrication and distribution. GSI’s goal is to make gem lab services as reliable and convenient as possible for leading companies in the gem and jewelry trade.

A GSI certified stone means that GSI has examined and graded the stone; the GSI certificate offers  most of the important information you should know about any diamond including:

  • The 4Cs: color, clarity, cut and carat weight
  • Characteristics: proportions, finish, treatments and more
  • Light performance (measuring the bright white light (brilliance), bright color light (fire) and scintillation (sparkle))
  • Inclusions map
  • And more



GSI offers several grading reports to meet client needs for different levels of format, detail and price.  Each report includes educational materials to help consumers understand the information in the context of personal jewelry and diamond purchases. You can read more about GSI grading here.  Additionally, you can read more about why you can trust a GSI certificate.

GIA offers several grading reports as well – more information on GIA grading may be found here.



The 4Cs of Diamonds – cut, color, clarity, and carat weight – are the most important characteristics to understand when evaluating a diamond.

A diamond grade is an exact scientific assessment of a stone’s quality and characteristics. A grading report shows not only the 4Cs, but also a diagram of each diamond’s inclusions.

Getting a diamond grade – and certification- can help any consumer feel consident and secure in a diamond purchase.

Click here for more information about the history of diamond grades.

Click here for more information about how to read a diamond grade.