When it comes to certifying diamonds, you’ll typically hear GIA and IGI a lot. But what’s the difference between the two certifications? Is one better than the other? Are they both different standards?
In this post, we’ll dive deep into the differences of GIA vs IGI certified diamonds, and why they’re so important when purchasing your engagement ring.
Table of Contents |
What is GIA? What is IGI? What Are The Main Differences Between GIA and IGI? – GIA and IGI In Grading The 4C’s Type Of Reports To Look At For IGI and GIA Diamonds Final Thoughts |
Related: Best Engagement Rings For Couples On A Budget – Under $2500.
What Is GIA?
GIA stands for “Gemological Institute of America”. The GIA is a non-profit research organization based in Carlsbad, California in the year 1931.

Their purpose was to research, educate, and grade natural gemstones. Since there was no official method of diamond grading at the time, they decided to make their own standard to diamond grading.
So in 1953, they created the International Diamond Grading System which ranks and grades a diamond based on the 4C’s (cut, clarity grade, carat weight, and color).
Check out our guide here to know more about the 4C’s and why they’re so important.
The 4C’s are now used by the entire diamond industry including the IGI (which we’ll get to in a moment).
The GIA also offers gemology training in 13 different countries across the world in various campuses, labs, and research centers.
Check out GIA certified diamonds at James Allen.
What Is IGI?
IGI stands for “International Gemological Institute”. The IGI is the world’s largest independent gem lab, with headquarters in Antwerp, Belgium. Yes, the same Antwerp where diamond-giant De Beers operates out of.
The IGI also has multiple offices around the world in places like Hong Kong, Dubai, Shanghai, New York, New Delhi, and Tel Aviv.
They employ over 650 gemologists and jewelry professionals to work on their diamond-grading capabilities, which makes the IGI a very reputable standard.
Want to check out an IGI certified diamond? Visit Clean Origin.
What Are The Main Differences Between GIA and IGI?
The main difference between GIA and IGI graded diamonds depends on where you are in the world and where the certification is more likely to be accepted.
Sort of like a driver’s test in different countries. Depending on which country you’re in, you’ll have to learn and understand the rules and signs of that respective country.
In places like Europe and Asia, IGI is widely recognized for their grading reports in the diamond industry.
However in recent years, GIA has slowly been increasing their market share in these regions.
When we take a look at USA and Canada, GIA is the most popular choice for graded diamond reports.
Related: The Truth Behind James Allen – Know This Before You Buy.
Some gemologists will say that the IGI has fewer strict grading standards compared to GIA. But this does not necessarily mean the IGI should be completely disregarded.
GIA and IGI In Grading The 4C’s
As we’ve mentioned before, some gemologists will say the IGI has looser restrictions. As a result, there are some inconsistencies in labs around the world that use the IGI diamond certification process.
When shopping for GIA and IGI diamonds, typically it’s safe to assume an inconsistency of 1 color grade from D-I colored diamonds. For diamonds colored J and below, the inconsistency is a lot less noticeable.
You can also expect a 1 grade inconsistency for diamond clarity from the Flawless to VVS range.
When shopping for IGI graded diamonds, make sure to double-check the clarity of SI1 and SI2 diamonds since many of them typically aren’t eye-clean with no visible inclusions and flaws.
On a more positive note, approximately 10-20% of IGI graded diamonds are still consistent with the GIA diamond certification. But the IGI may not have the same level of consistency in reporting as the GIA grading report.
As a result, unless you’re getting a once-in-a-lifetime deal on lab grown diamonds or natural diamonds, you may not be getting a fair price on an IGI-graded diamond as compared to a diamond with a GIA diamond certificate since the restrictions are tighter with GIA grading.
In other words, since the IGI is a lot more lenient compared to the GIA, a diamond retailer would be more incentivized to sell lower-quality diamonds through the IGI grading report as opposed to the more strict GIA certificate.
Types Of Reports To Look At For IGI and GIA Diamonds
The GIA offers full grading reports for diamonds of all sizes, as well as documentation (dossiers) for smaller diamonds.

On the other hand, IGI offers two types of diamond documentation for diamond grading reports: mini-reports and full grading reports.

It’s important to note that the IGI mini-reports are often given to vendors and diamond retailers in malls. These reports are unlikely to have lots of information compared to GIA documentation.
If you are looking for IGI certified diamonds, make sure to buy one with a complete IGI report issued by a reputable lab in the U.S. or Antwerp.
Related: James Allen vs Clean Origin: A Head-to-Head Comparison.
Final Thoughts
To sum it all up, when it comes to diamond grading, the GIA and IGI are two of the most popular methods of certifying diamonds in the market.
The GIA, founded in 1931, brought to the world their International Diamond Grading System which we now more commonly know it as the 4C’s (cut, clarity grade, carat weight, and color).
The IGI on the other hand, is the world’s largest independent gem lab spanning across multiple countries and employs over 650 reputable gemologists and diamond professionals.
The GIA is considered to be more strict in its grading methods which makes it the preferred diamond grading system in the U.S. and Canada. Whereas the IGI is more widely recognized, spanning over Europe and Asia. But the caveat is that they’re more lenient on their restrictions.
We can’t say one is better than the other because it really depends on where you are in the world when purchasing a diamond. If you’re in North America, we recommend looking for GIA certified diamonds. As for the rest of the world, IGI certified diamonds are your go-to.
Related: The Best Place To Buy Affordable Lab Grown Diamonds.