The IGI (International Gemological Institute) and GIA (Gemological Institute of America) use different grading standards, equipment, and methodologies. GIA is known for its stricter grading criteria, while IGI adopts slightly more lenient, commercially friendly standards. This often results in IGI grades being 1-2 colour grades higher than GIA for the same diamond—for example, a "G" colour grade from IGI might be graded as "H" or "I" by GIA.
However, this variation does not impact the physical or visual quality of the diamond. It reflects differences in grading perception and criteria between the two institutes, and not the diamond’s actual characteristics.
Importantly, while the 2-colour grade difference is a common observation, it may not apply to every diamond. Some stones may align more closely in grading between the two labs.
How does Nivoda handle this variation?
At Nivoda, transparency is key. While this grading difference is a known industry practice, we flag it only if you specify it in your QC preferences. This approach ensures we address your needs while maintaining efficiency in our processes. Add your own QC comments at checkout for your orders.