When buying a diamond, you need to consider more than just the 4Cs. You also need verify the diamond’s certification. While we recommend that you purchase one that has been certified by the GIA (Gemological Institute of America), there are a few questions that frequently arise during this stage of the purchasing process.

Some commonly asked questions:

Are there more institutes that give diamond certification?

Why is GIA recommended as the best?

Why is diamond certification so important? What purpose does it serve besides determining a diamond's worth?

What are the differences between the certifying organizations?

We understand that sifting through the diamond certification process can be overwhelming. Here's what you need to know.

Institutes That Provide Certifications


Gemological Institute of America (GIA) is a nonprofit organization founded in 1931 dedicated to gemology research and education. They strive to protect both buyers and sellers. In 1953, they introduced a letter-based grading system. Today, they are the top reputable certifying group.

American Gem Society (AGS) is operated and funded by an industry trade group. AGS is close to GIA in regard to its certification grading scale, but is less strict. Unlike GIA, which uses a letter-based grading scale, AGS uses a 1-10 number scale to grade diamonds.
Fun Fact: both GIA and AGS were started by Robert M. Shipley,
who fought to start and grow these organizations into what they are today.

European Gemological Laboratory (EGL) is more prominent in Asia and the European Union. The organization has been banned in the United States, and this is not a certification that we work with. If you are thinking about purchasing a diamond with this certification, contact us. We're here to help.

Gemological Science International (GSI) was founded in New York City in 2005. They originally planned to profit from companies appealing to large retail chains. They offer grading and appraisal services. However, their grades are inconsistent and unreliable.

International Gemological Institute (IGI) was established in 1975. Since then, they have become the largest independent gemological laboratory in the world, with offices ranging from New York to Hong Kong. However, the IGI grading system is three grades off from GIA certifications.

Why are Diamond Certifications Important?

You want to know your diamond. Like buying a home, purchasing a diamond is a significant, long-term financial investment. As a result, you'll want to know the details of your diamond inside and out, including its value and how much it will cost. When you buy a house, you get the deed. The certification is the diamond's "deed." It is your safety net as a consumer.

What We Recommend

We recommend only purchasing diamonds that have been certified by GIA. If you have any questions, ask us! We're here to ensure that you know exactly what you're purchasing. This will protect you and your investment.

Recommended Vendors

Blue Nile

Blue Nile is the largest well-known internet jeweler in the United States.

read our review

James Allen

One of the largest privately-owned online diamond retailers in the world.

read our review


Known for its “A Cut Above®” series of high-quality diamonds.

Read our review

Brian Gavin

Renowned expert when it comes to maximizing the brilliance of a diamond.

Read Our Review

Brilliant Earth

Cutting edge technology in providing customers with diverse conflict-free and environmentally safe diamonds.

Read Our Review