Diamond certification industry is not exclusive for GIA or AGS, yes they are the most reputable & known labs, but there are tons of certification labs out there, with less popularity than the beforementioned two.

We know for sure that a lot of these labs are just amateurs (Hi Mr. EGL), while others are much better and follows decent scientifical methods in assessing/grading diamonds, and of these are IGI labs.

If you’re getting your diamond from Blue Nile, you won’t see any mention for IGI, but if you’re shopping at James Allen, you will probably notice that they are introducing more collections of IGI diamonds that you can check here (Currently, JA has +11000 IGI diamonds).

While not many other online stores sells diamonds certified by IGI, but we believe that since James Allen (being the largest online diamonds  store for with +200000 diamonds) started listing IGI diamonds, they are worth a review, and then a comparison to the reputable GIA.

When it’s about buying a diamond, one of the most important things to consider is what certificate comes with this diamond, or to be precise: which certification lab has assessed the diamond and graded it accordingly?

Why do you need to count on this very much? More than ANY other factor, more than the Cut (even if it’s the most important factor among 4Cs)?!

Because simply if a lower quality lab (Yes, like EGL) grades a diamond with a G-Color, while it’s an I or J for GIA, then you’ve purchased the wrong diamond, regardless of anything you’ve been recommended to get!

This post will go over IGI as being a kind of controversial lab, it’s for sure has a good reputation these days, but why the giant Blue Nile (and others as well) didn’t take any step toward listing diamonds graded by IGI?

Let’s see!

What are IGI Certification Labs?

IGI (which stands for International Gemological Institute) was founded back in 1975 in Antwerp (Belgium), the labs were founded as diamonds, colored gems and jewelery certification institute.

Although Antwerp is considered the “home of diamonds”, IGI is considered the oldest certification lab there.

They offer grading services for almost all types of diamonds & jewelry, including natural diamonds, lab-grown, Hearts & Arrows, colored, etc.

IGI puts specific standards and methodologies to asses & grade diamonds, and this is applied across all their offices, so it’s less likely that a diamond will be graded differently from an IGI lab to another, they all follow the same grading & certification process.

While this looks obvious, but it’s not all the times, for example, you might be able to find some differences in grading levels for diamonds certified by EGL, as EGL has many offices around the globe.

Every lab of these is owned by someone (it’s like a franchise for diamonds certification labs, a McDonald’s but for grading diamonds!), this differences in grading can be seen there, but not in IGI.

IGI New LogoIGI Locations/Offices:

IGI presence went exponentially, although they have started in Antwerp, they now have offices in Antwerp, New York, Hong Kong, Kolkata, Tel Aviv, Mumbai, Bangkok, Tokyo, Dubai, Toronto, Los Angeles , Surat, Chennai, Ahmedabad, New Delhi, Thrissur, Jaipur,  and Hyderabad, and has more than 650 gemologists in their offices.

IGI brands itself as the largest organization of its kind, meaning that they are the largest “international” labs, as they are located in many countries, but this needs more explanation (from them), because GIA has 3000 gemologists and they have offices in 13 countries, so it’s not quite sure what they mean by largest here.

Update: It looks IGI has slightly changed the headline for their website from “Largest organization of its kind” to “World’s largest Independent Gemstone Grading Laboratory”, which explains a bit what they mean by that.

IGI Schools of Gemology

IGI has a School of Gemology as well, with 14 offices in Antwerp, Mumbai, Delhi, Hyderabad, Surat, Dubai, Shanghai, Ahmedabad, Chennai, Rome, Cavalese, Ascoli Piceno, Trecastagni, and Marcianise, where they offer diamond training and certification skills.

Their website mentions that they graduate thousands of jewelry professionals every year.

IGI is FOR Profit

Unlike other labs like GIA or AGS, IGI is a company (for-profit), and it was kind of a family business (by the Lorie family) for all its lifetime, until recently in late 2018, when the Chinese conglomerate Fosun acquired 80% of IGI (some resources mention that the deal was close to €100 million!).

IGI vs GIA Diamonds Grading Review

First, let’s have a quick comparison between both labs (as independent institutes), then we see the technical differences between IGI & GIA grading procedures.


IGI was established in 1975, where GIA was established in 1931!


GIA is a non-profit organization (so no one is getting rich by grading diamonds), while IGI was founded as a family business, and recently (2018) sold 80% of the “company” to Fosun Group (Shanghai-based company).

Number of Employees

IGI staff consists of 650 employees (gemologists, appraisers, office personnel), while more than 3000 people work for GIA.


GIA has 14 locations, while IGI has 18.

Now let’s get to some technical comparison between GIA and IGI:

In our own assessment & comparison of diamonds that have been graded by GIA & IGI, we’ve seen a slight upshift in grading some diamonds characteristics, mainly in diamond clarity & color.

A diamond that has been graded as an SI2 by GIA might be graded as SI1 by IGI, similarly to color, a J-color diamond (as by GIA) can be seen graded as K by IGI.

We’ve seen in our EGL Labs review that their diamonds should not be an option for any buyer, they inflate color & clarity levels with two or even 3 grades, some might say: Okay, IGI doesn’t do that, it’s maximum by one grade, and this is not “a big deal”!

We won’t say that it’s “not” a big deal, neither it is! That depends on the specific diamond, your intention of getting it (are you willing to resell anytime for example?), will you get an insurance for it?

But generally, getting a diamond with grades that are higher than its actual grades (even 1 grade difference) is not recommended, because:

1- You are paying an extra amount of money for a higher grade that doesn’t exist, to make it clearer, this is not the case all the time, IGI diamonds are cheaper than GIA, because “they know” that they are not as reliable as GIA, so you won’t be paying more money all times.

2- When you want to sell the diamond, it won’t be easy to convince a seller with a diamond other than GIA or AGS.

3- Even if you were able to sell it, you will also lose more money.

4- Most diamond insurance companies generally cover diamonds that are certified by either GIA or AGS.

One very important note here, these differences were found in high clarity grades (VVS2 and above), same goes for color.

So if you’re getting a an SI1 or VS2 clarity diamond, and/or color within I-G, most probably it won’t be an issue, but it has to be inspected individually to make sure it’s a good deal, since IGI diamonds are known to be a little cheaper than GIA.

If you found two diamonds graded the same color & clarity (one by GIA & another by IGI) for the same price, it will be a wiser option to pick the GIA diamond as the IGI in this case might be a bit over-priced.

IGI Grading & Reporting Services Review

As an organization specialized in gemstones & diamonds grading, IGI has many reports that show different characteristics of a diamond or other jewelry pieces, we will take a look at some of the most popular reports provided by GIA:

1- Loose Diamonds Report:

Like any other certification for diamonds in the industry (GIA, AGS, or others), this report assesses the diamond characteristics, and assign grades based on their standards, this report lists diamonds 4Cs, what Shape the diamond has, Polish, Symmetry (with its details like measurements, table & depth, etc.), and fluorescence.

Read: Is Diamond Fluorescence Good or Bad?

It also includes a graphic representation for the diamond itself which shows inclusions found on the diamond, here is a sample for a diamond report by IGI:

2- Hearts & Arrows Diamonds Report

This diamonds type is becoming more popular now, with the big online retailers have introduced new lines of products and branded them as unique & spectacular diamonds with unmatched cut grade.

We’ve seen this in James Allen collection named True Hearts™, while their biggest competitor named the collection Astor™ By Blue Nile, and recently, the premium quality store Whiteflash jumped into this with their A CUT ABOVE® collection.

Because of this demand, and since GIA doesn’t include any specific details about these branded collection in the certificate, it became an opportunity for labs like IGI to issue grading report for diamonds with Hearts & Arrows (premium cut).

IGI uses Hearts & Arrows gemscope to check if ALL diamond facets aligned to appear correctly, which means full symmetrical proportion to the diamond, the report is identical to the previous report, except it has a comment section to confirm that this diamond is a Hearts & Arrows one, like this one:

IGI Sample Hearts & Arrows Report

3- Colored Diamonds Report

IGI offers a service to grade and provide detailed assessment of colored diamonds as well, since colored diamonds are examined & assessed differently from the colorless diamonds we’re familiar with.

Why this report is important to be a separate one?

Because a lot of “fake” colored diamonds are actually colorless with low color grade, but they have been treated to alter the diamond’s color!

The Colored diamond report by IGI gives many details about the diamond color; its origin (natural or treated), grade, distribution, and a comment section, like this one:

IGI Colored Diamond Report

4- Synthetic / Lab-Created Diamonds Report

Lab-created diamonds are becoming more adapted in the past few years due to financial matters mainly, people are looking for cheaper options for almost everything out there, and diamonds are no exception.

You might think that it’s easy to identify a lab-created diamond, so why people would go for it? Actually, it’s not, NO one can detect the difference between a natural diamond vs. a synthetic one by just looking at it.

In regard to the IGI report for the lab-grown diamond, it’s identical to the natural diamond report, except it has a line that clearly states that this diamond is “Laboratory Grown”, and report name of course.

5- Other Reports by IGI

The above reports are the most popular reports that IGI offers (and what people look for actually), but IGI has more reports as well, which are:

  • Jewelry Report
  • Colored Stone Report

We will not go into details about these, and will refer you directly to their respective pages on IGI here & here.

IGI Diamonds Grading & Reports Review, Are They Reliable?

Now it comes to the good question: How reliable are IGI reporting services?

Are IGI-certified diamonds good? Recommend to buy Them? Or we need to look for a better lab?

In certification labs, some names are very strict and follow unmatched standards, like GIA & AGS, while some others are much less about that, they have very “lenient” standards (like EGL!).

And in between those, a very wide range of certification labs come, they have a straight-forward guidelines to grade & assess diamonds, but they might not be as strict as the big names (GIA & AGS) in the industry, due to a lot of reasons, mainly the inspection tools they have, and the expertise of local gemologists they work with.

And in a lot of cases, the “for-profit” companies tend to be on the seller side rather than the buyer!

Because at the end of the day, it’s their business, and being a profit-driven forces these companies to let sellers love their grading process (so they send more diamonds to be graded by IGI).

This makes a little bit of less-consistency in their diamonds grading, as an example, GIA might grade two diamonds clarity with VS2, but in certification labs those with less restrictions, they might grade one as VS2 and the other as VS1.

Read: Diamond Certification: How to Read a Diamond Grading Report?

IGI comes in this range, they are a good-reputable certification lab, and follow well-structured guidelines to assess diamonds, therefore, some of the big online stores sell IGI-certified diamonds, namely JamesAllen as you can see here, while BlueNile or Whiteflash still don’t offer IGI diamonds.

We can’t clearly say Go or No Go for an IGI diamond, it depends on many other things, we’ve seen diamonds by IGI that are priced reasonably, while other diamonds were priced like a GIA-graded diamond with same specifications.

Here you have to be careful in picking the correct diamond JUST IF the price makes sense.

Final Word on IGI-Certified Diamonds, Are They Good?

After what we’ve seen above, and although JamesAllen does sell IGI-certified diamonds, we can’t always suggest to go with IGI diamond, it has be inspected, matched with similar diamonds from GIA or AGS, are the same price? Or you’re getting a cheaper deal on it?

Is it from high grades color & clarity? In many cases, we’ve seen the inflation of grades in IGI happens on lower clarity (SI2 & SI1) & color (I & J) grades.

Our top recommendation on diamonds is always to get a GIA or AGS diamonds (with GIA being the first option because it’s simply the best certification lab out there), from well-known online stores like JamesAllen, BlueNile, and if you’re looking for a top-quality premium diamonds, head directly to Whiteflash.

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