Lab Grown Diamonds Certification & Why it Matters (in 2025)

Last Updated on November 11, 2025 by Learning Jewelry

Wondering about certifications for lab diamonds?

Perfect!

Youโ€™re in the right place.

In this Learning Guide Iโ€™ll answer these questions and more:

lab diamond certification

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

What is aย 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 theย best diamond storeย in our reviews.

They can also be calledย diamond grading reports.ย 

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.ย 

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

A standard diamond certification or grading report usually has:ย 

  • 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.ย 

Remember, a laboratory grown diamond is a real diamond.ย 

Read also:ย Best Place to Buy Lab Diamonds

Do You Need A Lab Diamond Certificate?ย 

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 donโ€™t come withย grading reports.ย 

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.ย 

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

I didnโ€™t even know how important diamondย certificates were when I worked there because we didnโ€™t have many. We werenโ€™t taught to talk about that, only the positives.ย 

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

Essentially, a diamond grading report lets you know that youโ€™re getting exactly what youโ€™re paying for.ย 

Let me explain.ย 

If you shelled out $9,000 on aย 2 carat, VVS1, ideal cut, and Eย color graded lab diamond, you want to know your diamondย isnโ€™t worse grades.

By the way if you arenโ€™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

Thatโ€™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.ย 

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

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

How mad would you be?ย 

Iโ€™d be pretty ticked. Letโ€™s dig into it a bit moreโ€ฆ

Are Lab Diamond Certifications the Same?ย 

Not all diamond certifications are the same. They may provide the same information, but they donโ€™t all hold the same standards.ย 

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

For natural diamonds, we only recommend buyingย gradingย reports from the GIA or AGS laboratories.ย 

Read also:ย 4 Grading Labs To Avoid for Natural Diamonds

A gemย 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.ย 

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

Aside from standards, some lab diamond certifications arenโ€™t as detailed. Up until recently, GIA diamond certifications werenโ€™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 wasnโ€™t as detailed as youโ€™d find on an IGI lab diamond certification.ย 

Different Grading Labs for Lab Diamond Certificationย 

GIA Lab Diamonds

The GIA is the worldโ€™s leading authority on all things diamond and gemstone in addition to providing diamond certifications.ย 

As mentioned before, GIAโ€™s lab diamond reports werenโ€™t as detailed prior to 2020. They didnโ€™t include finite details about the diamond.ย 

Before, a GIA lab diamond certification didnโ€™t tell you which creation method was used. Lab diamonds are created usually by the CVD process or the HPHT process.ย 

Read also:ย How Are Lab Diamonds Made?

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 buyerโ€™s decision.ย 

In 2020, the GIA revamped their lab diamond grading reports include missing details. Because itโ€™s happened recently, there arenโ€™t too many retailers that carry GIA certified lab diamonds.ย 

Our favorite places to buy GIA lab diamonds Blue Nileย and Brilliant Earth.ย 

Read also:ย Where to Buy GIA Certified Diamonds Online

gia report lab

IGI Lab Diamonds

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

IGI certified lab diamonds are the most common youโ€™ll run into. While a natural diamond IGI grading report doesnโ€™t meet gold standard, their lab diamond certificates are highly esteemed.ย 

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

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.ย 

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.ย 

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

The major difference between a GIA diamond certificateย and an โ€‹AGS diamond certificate is the diamond cut grade for round shapes. You mightโ€™ve heard the term โ€œideal cut diamondโ€ or even โ€œsuper ideal cut diamondโ€.ย 

Some retailers will distinguish an Ideal Cut labeled diamond from an Excellent Cut Diamond. You might find yourself buying a diamond labeled โ€œideal cutโ€, but on the GIA report, it says Excellent Cut.ย 

The two are synonymous, but the AGS uses the term โ€œidealโ€ 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.ย ย 

Read also:ย What Are The Different Kinds of Inclusions?

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

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.ย 

The GCAL is newer than those labs aforementioned, having opened in 2001. They headquartered in New York Cityโ€™s Diamond District.ย 

Previously, Iโ€™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.ย 

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

These are basically the same things as ASETย and Idealscopeย images with Whiteflashโ€™s diamonds. . They allow you to see a map of the light coming in and reflecting out of theย diamond, citing any leakage of light. It also will show you how precise your proportions are by forming a shape of the star.ย 

Itโ€™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.ย 

GCAL-guaranteed-lab-grown-diamond-grading-certificate

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, theyโ€™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.ย 

I donโ€™t recommend buying HRD at all, whether youโ€™re looking for a lab diamond or a mined diamond.ย 

That goes the same for those of you in Europe. Theyโ€™ll be readily available in your neck of the woods, but Iโ€™d go for one of the other lab grading certificates mentioned.ย 

Instead of having I1, I2, and I3 clarity grades, an HRD certificate will show P1, P2, and P3 for pique. Itโ€™s a different terminology but is the same as Iย clarity grades.ย ย 

HRD-lab-diamond-grading-sample-report_b853d5d2-4c56-4952-aff1-a02cdbec95fb

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.ย 

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.ย 

diamond-foundry did you know - GIA gemologist

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

Thereโ€™s a few problems I have with Diamondย Foundry lab diamonds. The first being theyโ€™re difficult to find. They have very few partners, mainly because theyโ€™re trying to direct people to buy directly off their site.ย 

Itโ€™s a branded diamond certification, so theyโ€™re also able to charge more, which is a complaint from customers.ย 

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. Itโ€™s difficult to find a lab diamond with better than G color, which could be a problem for some.ย 

I personally donโ€™t recommend Diamond Foundry lab diamonds because there are much better grading authorities who arenโ€™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.ย 

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 thatโ€™s only because theyโ€™ve started to bring in lab diamonds to the cases.ย 

I donโ€™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.ย 

GSI Grading Report

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

What Is The Best Lab Diamond Certification?

The top labs for synthetic diamond gem certification are:ย 

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