Certifications
There are many grading labs around the world. Each lab uses its own grading system and nomenclature. As a result, a report from one institute might show different results from a report issued by another lab for the same diamond.
The top 4 major gemological labs in the world are GIA, AGS, EGL, and IGI.




Gemological Institute of America
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American Gemological Society
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European Gemological Laboratory
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International Gemological Institute
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