Home » Diamonds » EGL vs. GIA Diamond Certifications: How Do They Differ?

EGL vs. GIA Diamond Certifications: How Do They Differ?

We’re reader-supported. Posts may contain links that provide a commission at no cost to you. Learn how we make money.

EGL vs GIA Diamond Certifications

When you’re examining a diamond for its quality, it’s nearly impossible to verify with your naked eye what the salesperson is telling you. If they were to claim a diamond is a G color, meaning it’s “near colorless,” how would you know they’re telling the truth?

The solution to this problem is a diamond grading report from a reputable organization.

Two of the most popular organizations that provide diamond certificates are the Gemological Institute of America (GIA) and the European Gemological Laboratory (EGL). 

In this article, we’ll explore what diamond certificates are, what you should know about the GIA and EGL, how each certificate impacts price, and why the GIA is the right choice for certifying your diamond.

What to Know About GIA Certifications

The GIA is the preeminent organization when it comes to verifying the quality of diamonds. They’re an independent nonprofit that researches all types of gems and educates professionals in the industry. 

Best known for developing the four Cs of buying a diamond (clarity, color, cut, and carat), the GIA doesn’t actually determine the value of diamonds.

Instead, the GIA provides an objective report of its features, and then the market sets the price based on those grades. 

For example, if the GIA grades a diamond as an E color (colorless), it will likely sell for more than one graded H (near colorless), if all other qualities are equal.

The way the certification process works is a diamond is shipped to a GIA office, and any identifying marks are removed to ensure objectivity. 

The graders first test the authenticity of the diamond to know whether it’s natural or lab grown. This is a foundational test, because natural diamonds sell at a premium over lab created diamonds, even if all other characteristics are the same.

It’s then assessed along the four Cs. One key factor examined here is whether the diamond was treated with any clarity-enhancement procedures. 

If there were any modifications to the diamond in order to remove inclusions and improve its appearance, these are noted in the report and will decrease the value of the diamond.

Next, gemologists measure the cut by examining its dimensions, facet, and degree of brilliance.

Finally, they weigh the diamond to determine its carat.

These qualitative and quantitative measurements are compiled in a grading report that tells buyers all they need to know about the quality of a diamond.

For example, Blue Nile, an online diamond retailer, includes the GIA report for all their diamonds. You can view the report for this 1.01-carat round cut diamond and be confident in its excellent polish and symmetry, F color grade, and more.

GIA Report

The GIA can also inscribe a diamond with a serial number. The inscription is invisible to the naked eye and doesn’t affect light performance. The number matches the one on the report, so you can verify it’s the correct diamond.

What to Know About EGL Certifications

The EGL is an independent network of gemological laboratories, with offices around the world in places such as New York, Miami, Europe, Canada and Israel. Founded in 1977, the EGL offers a similar service as the GIA — grading diamonds along the characteristics that determine their overall value.

EGL Report

If the GIA is the established, credible organization for grading diamonds, why has the EGL also been successful in sustaining its business for many decades?

It’s because the EGL takes advantage of the GIA’s shortcomings. For example, a GIA certification is expensive, so jewelers can save money by opting for the EGL. 

Secondly, there’s turnaround time. Jewelers want faster turnaround on the grading process so they can sell the diamonds sooner. Having inventory tied up at the GIA is costly.

Thirdly, the EGL offers a pre-certification option, which doesn’t require jewelers to pay for the certificate after it’s been graded. 

If the grade is poor and the diamond likely won’t sell for a high price, they can save money by not having the certification printed.

Lastly, the EGL is commonly used to grade diamonds under one carat.

It’s important to know that some in the industry believe EGL has looser grading standards than the GIA. In general, the EGL reports diamonds as having a higher grade than the GIA.

We’ll dive into specifics below, but the end result to be aware of is you could pay significantly more for an EGL diamond than a GIA one because the EGL report could claim it’s of higher quality.

EGL USA vs. EGL International

Because the EGL is an independent network, all the businesses operate separately. That means if you were to send the same diamond to multiple offices, you could get different results.

Diamond industry experts express more confidence in the USA locations than the international ones. Some have such little confidence in the international offices.

How GIA Grading Compares to EGL

EGL vs GIA Infographic

There’s an easy way to test diamond grades from the GIA versus EGL: Send the same diamond to both organizations, and compare the results across each measurement. 

Many jewelers have done just that, and the industry has come up with some general guidelines on how to interpret EGL results compared to the GIA

In this section, we’ll provide examples of what you can expect comparing grades across clarity, color, carat, and cut.


Clarity measures the size, placement, color, and degree of inclusions in a diamond. Inclusions are defects within a diamond that impact its performance, and if they’re large enough, they can be seen with the naked eye. They make diamonds less valuable.

The jewelry industry generally believes the EGL grades clarity one or two levels higher than the GIA. For example, this 1.00-carat round diamond from James Allen is graded by the GIA as VS2 clarity.

1.00 carat round diamond - James Allen

It’s the lower tier of “very slightly included,” which means there are inclusions, but they likely aren’t visible to the naked eye.

Were this diamond graded by the EGL, the expectation is it would be graded VS1 or VVS2 (very, very slightly included). Each of those would increase the perceived value of the diamond. If you were paying for the diamond based on the EGL report, it’d be more expensive.


The GIA’s highest tier for color is “colorless,” and the scale works its way down to “light,” which means it has a strong yellow tint. Using our same diamond from above, with an H color grade from the GIA, you’d expect it to be graded a G or F by the EGL.

The potential jump to F illustrates an important principle. An F color means the diamond is in the colorless tier, as opposed to near colorless, where G falls. That determination can result in a significant price increase because there’s a premium to be paid for a colorless diamond.

If the grading standards are more loose, and it’s designated colorless, that misrepresentation is costly because you’re paying the premium without getting a true colorless diamond.


Carat is an objective measurement of a diamond’s weight, so there’s no room for subjectivity. When it comes to comparing GIA versus EGL in regard to how they measure carats, you don’t need to be concerned about different results. 

There isn’t any concern the two organizations have different standards for carats.


The most significant differences between the GIA and EGL are often clarity and color, but those principles can apply to cut as well.

Cut is what determines a diamond’s sparkle and brilliance, so a mismeasurement on cut means your diamond won’t have the glimmer you expect. 

It’s often considered the most important of the four Cs, so any lack of light performance can really affect its overall quality.

How Each Certificate Impacts Price

The organization that certifies the diamond impacts the price on two occasions: its initial sale price and the potential resale price. Let’s start with the initial sale price.

If the consensus is true in the case of the diamond you’re considering buying, you’ll pay more for the exact same diamond if it’s graded by the EGL and not the GIA. That’s because the EGL grades will likely be two to four total grades higher (if you combine the increases across color, cut, and clarity).

Let’s take this example of a diamond from Blue Nile, with the following grade from the GIA:

  • Carat: 1.00
  • Cut: Good
  • Color: G
  • Clarity: VS1
  • Price: $4,667

1.00 carat round cut diamond - Blue Nile

If we moved three total grades up the GIA scale, and instead made the cut very good and the color E, the least expensive option available is $5,641. That’s a 21 percent difference and close to $1,000 in total.

This illustrates the importance of reliable grading that doesn’t overvalue the diamond’s qualities.

The second way certificates impact price is during a resale. Jewelry buyers know the difference in grading standards, so the resale value of an EGL diamond is often less than a GIA diamond. 

That means you overpay when you buy it and get less money back when you sell.

Why is GIA the Right Choice?

A diamond graded by the GIA is the right choice because they’re considered the most credible organization when it comes to determining the quality of a diamond. 

If you were to line up multiple diamonds of differing quality for the average consumer, they’d have a difficult time ranking them top to bottom.

A report from the GIA solves this problem and ensures you’re getting what you pay for. You can be certain you aren’t overpaying for a diamond in regard to its quality, and when the GIA designates it a certain color, cut, or clarity, that’s its genuine grade.

It’s all about giving the buyer confidence. Limiting your options to GIA diamonds means it’ll be a more fair exchange on the initial purchase and resale.

But if you do choose an EGL diamond, ensure its qualities align with what’s on the report.

Devon Tyler

Devon Tyler

Devon Tyler is the founder of TeachJewelry.com.

He earned an Applied Jewelry Professional Diploma from the Gemological Institute of America and now brings you essential information about diamonds, settings, and more.

Devon has consulted with leading jewelry brands, and his work has been cited in Diamond Nexus and other industry publications.

He's also a member of the International Gem Society.

Devon enjoys discussing jewelry with readers, so contact him with any questions at tyler.devon@teachjewelry.com.

Learn More About Devon