Lab Grown Diamonds Certification & Why it Matters (in 2023)

Last Updated on August 23, 2023 by Juli "Jewels" Church

Wondering about certifications for lab diamonds?


You're in the right place. 

In this Learning Guide I'll answer these questions and more: 

lab diamond certification
  • What is a diamond certification?
  • Do you need a grading report for lab diamonds?
  • What’s the best certification for lab diamonds? 
  • What lab diamond certification labs are there?

What is a Diamond Certification?

A diamond certificate is a document that comes with a loose diamond or diamond engagement ring. The document is provided by a gemological laboratory in the jewelry industry. Naturally such certifications are crucial when buying online from any store that wants to contend as the best diamond store in our reviews.

They can also be called diamond grading reports. 

Certificates show a diamond buyer how that diamond has been graded using the 4Cs of Diamond Quality: Diamond Cut, Diamond Clarity, Diamond Color, and Diamond Carat Weight. The 4Cs was put in place by the Gemological Institute of America. 

The minor details on a grading report may vary by lab, but most of them have the same structure. 

A standard diamond certification or grading report usually has: 

  • Diamond Shape
  • Cut Grade
  • Color Grade
  • Clarity Grade
  • Carat WeightF
  • Polish
  • Symmetry
  • Proportions
  • Measurements
  • Fluorescence
  • Treatments
  • Diamond Plot
  • Grading Scales
  • Laser Inscription

A lab diamond certification may also include which creation process was used to produce the lab grown diamond

Remember, a laboratory grown diamond is a real diamond. 

Do You Need A Lab Diamond Certificate

You might be wondering, why do I even need a lab diamond certificate to begin with?

After all, the majority of top diamond engagement rings in popular brick and mortar retailers don’t come with grading reports. 

When I worked at Kay, we had 6 certified GIA diamonds in their (unbranded) Now and Forever Collection. The other 8 were part of the Tolkowsky and Leo collections. 

Did I mention, there were over 85 engagement ring choices in that case? 

I didn’t even know how important diamond certificates were when I worked there because we didn’t have many. We weren’t taught to talk about that, only the positives. 

But the truth is, you really need a lab diamond certificate, especially if you’re buying a lab diamond with high diamond grades. 

Essentially, a diamond grading report lets you know that you’re getting exactly what you’re paying for. 

Let me explain. 

If you shelled out $9,000 on a 2 carat, VVS1, ideal cut, and E color graded lab diamond, you want to know your diamond isn’t worse grades.

By the way if you aren't sure what exactly VVS1 means, you might want to read our article which explains what a VVS diamond is.

lab created 2.08 carat round diamond by James Allen

That’s where buying certified lab diamonds from the right authority comes in. Anyone can say they know how to grade diamonds, but reputation is everything. 

Some people have purchased diamonds that have been graded by multiple authorities. We’ve seen these come back with different grades on the same diamond

Imagine finding out that diamond you paid for turns out to be graded lower than what you were sold on by a more reputable lab. 

How mad would you be? 

I’d be pretty ticked. Let’s dig into it a bit more...

Are Lab Diamond Certifications the Same? 

Not all diamond certifications are the same. They may provide the same information, but they don’t all hold the same standards. 

There are more acceptable lab diamond certifications than there are for natural diamonds.

For natural diamonds, we only recommend buying grading reports from the GIA or AGS laboratories

A gem grading lab has its own standards on how they grade a loose diamond. Popular jewelry stores may provide grading reports that come from a cheaper lab that grades diamonds in bulk. 

Kay & Zales are notorious for doing this with GSI grading reports for their natural and lab diamonds. 

Aside from standards, some lab diamond certifications aren’t as detailed. Up until recently, GIA diamond certifications weren’t the most desirable grading reports for lab diamonds.

The GIA focused more on being the top natural diamond certifying lab. They still graded lab grown diamonds, but the information wasn’t as detailed as you’d find on an IGI lab diamond certification

Different Grading Labs for Lab Diamond Certification 

GIA Lab Diamonds

The GIA is the world’s leading authority on all things diamond and gemstone in addition to providing diamond certifications. 

As mentioned before, GIA’s lab diamond reports weren’t as detailed prior to 2020. They didn’t include finite details about the diamond

Before, a GIA lab diamond certification didn’t tell you which creation method was used. Lab diamonds are created usually by the CVD process or the HPHT process. 

Both creation methods can produce high-quality lab created diamond. However, there are some optical features like blue nuance and brownish tint that might influence a buyer’s decision. 

In 2020, the GIA revamped their lab diamond grading reports include missing details. Because it’s happened recently, there aren’t too many retailers that carry GIA certified lab diamonds. 

Our favorite places to buy GIA lab diamonds Blue Nile and Brilliant Earth

gia report lab

IGI Lab Diamonds

The International Gemological Institute is a very popular diamond certifying authority. You’ll run into more IGI certified diamonds online rather than in-store. 

IGI certified lab diamonds are the most common you’ll run into. While a natural diamond IGI grading report doesn’t meet gold standard, their lab diamond certificates are highly esteemed. 

They are recommended as the best grading certificates for lab grown diamonds. Of course, that’s before the GIA went and updated their certifications. 

Now the two stand neck and neck as leading diamond certifications for lab grown diamonds. They are most often recommended. However, as noted before, IGI lab diamonds are a lot easier to come across than the new lab diamond GIA certificates. 

IGI lab diamond report

AGS Lab Diamonds

The American Gem Society grading certificates are equivalent to a GIA grading report by standard. They are the only other grading report we recommend for a natural diamond

The AGS laboratory has lab diamond certificates, but they’re pretty difficult to find. Most online retailers have lab created diamonds with certificates from other grading labs. 

The major difference between a GIA diamond certificate and an AGS diamond certificate is the diamond cut grade for round shapes. You might’ve heard the term “ideal cut diamond” or even “super ideal cut diamond”. 

Some retailers will distinguish an Ideal Cut labeled diamond from an Excellent Cut Diamond. You might find yourself buying a diamond labeled “ideal cut”, but on the GIA report, it says Excellent Cut. 

The two are synonymous, but the AGS uses the term “ideal” officially. They patented the Ideal Triple 000. The AGS grades diamonds using a 0-10 scale. The 0 is the best, as there are zero inclusions.  

However, the diamond industry recognizes the AGS Triple 0 Ideal equal in quality to a GIA Excellent Cut diamond

GCAL Lab Diamonds

The Gem Certificate and Assurance Lab is another reputable laboratory grown diamond report certifying authority. Many of our recommended lab diamond retailers carry them. 

The GCAL is newer than those labs aforementioned, having opened in 2001. They headquartered in New York City’s Diamond District. 

Previously, I’ve asked around in the community of lab diamond certification authorities and many of my fellow International Gem Society members said they also recommend GCAL in addition to GIA and IGI lab diamond certificates. 

A GCAL certificate differs from other lab diamond certificates by including what they call an optical brilliance analysis and an optical symmetry analysis. 

These are basically the same things as ASET and Idealscope images with Whiteflash’s diamonds. . They allow you to see a map of the light coming in and reflecting out of the diamond, citing any leakage of light. It also will show you how precise your proportions are by forming a shape of the star. 

It’s not a necessary feature when buying a lab diamond, but some people choose GCAL because they like the extra details. You can also obtain ASET and Idealscope images for any center diamond


HRD Lab Diamonds

The HRD Antwerp grading certificate is a leading grading report for diamonds in Europe. HRD stands for Hoge Raad voor Diamant. This Russian phrase translates to The High Diamond Council, which is centered in Antwerp.

Though they claim to be the best of diamond grading labs in the world, they’re not valued as such in the United States or the western side of the world. Furthermore, many HRD synthetic diamonds with the same grades as GIA certified diamonds actually turn out to be more expensive. 

I don’t recommend buying HRD at all, whether you’re looking for a lab diamond or a mined diamond

That goes the same for those of you in Europe. They’ll be readily available in your neck of the woods, but I’d go for one of the other lab grading certificates mentioned. 

Instead of having I1, I2, and I3 clarity grades, an HRD certificate will show P1, P2, and P3 for pique. It’s a different terminology but is the same as I clarity grades.  


Diamond Foundry Lab Diamonds

Unlike the other grading reports, Diamond Foundry grades and produces man made diamonds themselves. They recently bought out the popular lab diamond company called VRAI. 

They also did away with IGI certification on their website to bring their own certificates into the mix. The Diamond Foundry grading certificates are produced by a team of GIA gemologists who are said to be certified in diamond grading. These are not GIA certificates. 

did you know - GIA gemologist

However, Diamond Foundry claims their GIA gemologist team is certified in diamond grading

There’s a few problems I have with Diamond Foundry lab diamonds. The first being they’re difficult to find. They have very few partners, mainly because they’re trying to direct people to buy directly off their site. 

It’s a branded diamond certification, so they’re also able to charge more, which is a complaint from customers. 

The last issue I want to point out is that a lot of people note that Diamond Foundry lab diamonds have worse color than others. It’s difficult to find a lab diamond with better than G color, which could be a problem for some. 

I personally don’t recommend Diamond Foundry lab diamonds because there are much better grading authorities who aren’t driven by a branded price. But if you want to check out some of their diamonds, our friends over at Brilliant Earth will have some in stock. 

GSI Lab Diamonds

Gemological Science International graded diamonds are more likely to be found locally at big name retailers like Kay, Zales, and Jared. Their GSI diamonds are mainly mined diamonds, but that’s only because they’ve started to bring in lab diamonds to the cases. 

I don’t recommend buy GSI diamonds at all either. My Tolkowsky engagement ring from Kay is a GSI graded diamond, which is pretty much worthless in the jewelry world when it comes to resale. 

GSI Grading Report

The GSI was created mainly so big name retailers could get diamonds certified in bulk for a good price. It’s not about their quality or standards, it’s about how much the companies can get without forking over too much cash. 

What Is The Best Lab Diamond Certification?

The top labs for synthetic diamond gem certification are: 

  • GIA Certified Lab Diamonds
  • AGS Certified Lab Diamonds
  • IGI Certified Lab Diamonds
  • GCAL Certified Lab Diamonds

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