GIA vs. IGI Diamond Certification: Which is Better?

Diamonds are often considered timeless gifts, especially since they are commonly used as the centerpiece in engagement rings. Because of this, you’ll probably buy a diamond at some point in your life. It’s important to understand how to choose the best one.

Being familiar with the 4Cs–cut, color, clarity, and carat weight–is essential, however it’s just as important to understand how diamonds are graded. Most diamonds come with a grading certificate detailing the 4Cs, along with other factors like proportions and fluorescence, all of which influence the diamond’s quality and price.

In the past, mined diamonds were the only option, but advancements in technology have introduced lab-grown diamonds as an alternative. These diamonds are created in labs but are visually and chemically identical to mined diamonds. They are an eco-friendly option for those who care about sustainability. As lab-grown diamonds became more common, grading labs had to adjust. Some traditional laboratories now grade lab-grown diamonds, while new labs have been established specifically for them.

Why Buy a Certified Diamond  

Diamonds are small but incredibly detailed. It’s difficult to spot their unique features without special tools such as a jeweler’s loupe or microscope, along with the expert knowledge that comes from extensive training. Since most people don’t have access to this equipment (nor the expertise), it’s smart to buy a diamond certified by a trusted lab. Certification ensures that trained gemologists have carefully examined the diamond and that you’re getting good quality for the price.

Diamond Certification Organizations  

Many organizations specialize in grading and certifying diamonds, and each one has its own standards. So, how do you know which one is the best? It’s helpful to learn about these labs and how they compare to one another. Let’s explore two specific labs today to evaluate which one may be the best choice for your diamond grading certificate, Gemological Institute of America (GIA) or International Gemological Institute (IGI).

GIA (Gemological Institute of America)

The Gemological Institute of America (GIA) was established by Robert M. Shipley in 1931. Shipley wanted to create a standardized scale for grading diamonds in order to make the jewelry industry more professional and trustworthy. During that era, every jeweler was grading diamonds however they saw fit. This made it difficult to truly understand what you were purchasing.

Not only did GIA create the standardized system, but they also offered training for jewelers to learn how to properly utilize it. It wasn’t until 1953 that the 4Cs system was introduced, along with the diamond grading report that we know of as modern day reports. 

GIA is recognized as the most trusted diamond grading organization in the world. GIA has essentially set the standard that many other labs abide by in terms of grading practices. They are considered to be consistent, reliable, and accurate in their diamond grading and have earned the trust of consumers, who consider GIA to be their top choice for diamond grading certificates.

GIA diamond grading reports contain not only the cut, color, clarity, and carat weight, but also a plot and descriptions of inclusions, proportions, symmetry, and polish details. Given that GIA is strict on their grading, they tend to not “overgrade” diamonds (i.e. give them a higher color or clarity grade than they deserve). This strict grading policy tends to increase the desirability and price of GIA graded diamonds.

Even when lab-grown diamonds became popular, GIA did not (at first) offer grading for lab-grown diamonds. However, starting in 2020, they began offering this service and now provide full grading reports for lab-grown diamonds, similar to those for natural mined diamonds.

IGI (International Gemological Institute)

The International Gemological Institute (IGI) was founded in 1975 in Belgium to provide diamond and gemstone grading in one of the world's largest diamond trading centers. IGI now has locations in other countries, including the United States and China. IGI became well known for their quick turnaround times and reliability for, not only natural mined and lab-grown diamonds, but also colored gemstones. IGI was the first lab to offer full grading reports for lab-grown diamonds, setting the standard for what consumers were to expect from other grading institutions. 

While IGI is well known as a trustworthy diamond grading lab, it is seen as less prestigious than GIA. GIA has been around much longer and is known to be quite strict with its policies, while IGI is considered quite a bit more lenient. Because of this, diamonds graded by IGI can be given a higher grading than they deserve (overgrading). Consumers are aware of this, so IGI certified diamonds usually have a lower cost than GIA graded stones. For this reason, consumers who are more budget-conscious may want to consider an IGI certified stone.

While IGI tends to overgrade their natural mined diamonds, they have been the leader in lab-grown diamond grading ever since these eco-friendly stones became popular. IGI diamond grading reports include cut, color, clarity, and carat weight, along with other stone specifications, though they are not as detailed as GIA reports.

GIA vs. IGI, Which is Best?  

Choosing between GIA and IGI certification ultimately depends on your personal preferences and budget. If you desire to purchase a diamond from the most trusted diamond grading organization with the strictest policies, GIA is the better option due to its consistency and higher resale value. Highly respected by the community, GIA is trusted by both jewelers and consumers who value high standards.

Alternatively, if budget is one of the more important aspects of your diamond search, then IGI is a perfectly appropriate choice. Although IGI certifications are not as highly sought out as GIA, they are still plenty thorough. Additionally, they have been and continue to be the leader in lab-grown diamond certifications. No matter which certification lab you choose, purchasing a certified diamond ensures you’re making a sound investment, backed by documentation from experts with extensive knowledge and training in the diamond industry. By understanding the strengths and weaknesses of GIA vs. IGI, you can select the one that best meets your needs and make an informed purchase.