GIA vs EGL vs AGS

When shopping for a loose diamond to complete one of our beautiful engagement ring or anniversary ring settings, one of the first decisions a consumer must make is the certification. Adiamor’s loose diamond selection is currently exclusively made up of certified diamonds evaluated by the GIA – Gemological Institute of America or AGS – American Gem Society.  We currently don’t offer EGL or EGL-USA – European Gemological Laboratory.

The result of your decision between a diamond from GIA or AGS vs EGL has a major effect on the characteristics of stones available to you, how much you spend, and how universally accepted your certification will be.

Who They Are

The Gemological Institute of America (GIA) and the European Gemological Laboratory (EGL or EGL-USA) are the world’s two leading gemological analysis laboratories.  AGS is a highly respected gemological lab, but not as commonly used as GIA.

All follow a rubric of diamond assessment that measures stones against an ideal version, but it was the GIA that first developed the “Four C’s” concept most people know of noting and ranking the four major traits of a diamond that make it the most attractive, strong, and valuable: cut, color, clarity, and carat weight. Once reserved only for the round brilliant diamond, over the years all three labs have opted to extend certification and grading services to include other popular diamond shapes such as the princess cut and cushion cut.

The GIA and the EGL are large diamond grading and certification labs but are markedly different in some key ways that often prompt jewelers and consumers to choose diamonds certified by the GIA.

What Makes GIA Different

GIA is known for having the most stringent and precise diamond grading standards in the world, granting high ratings to only the most superior diamonds that other labs including the EGL issue much more freely. This means that when two diamonds that receive comparable grading for cut, color, clarity, and other determinations of quality,  one from the GIA, and one from the EGL, the stone graded and certified by the GIA is invariably of higher quality than the stone receiving the same marks from the EGL.

GIA’s operations are broad in scope and geographically, featuring locations in all of the world’s major diamond-trading hubs. The organization also boasts educational campuses in 12 cities where educational certificate programs for aspiring gemologists, designers, and professional jewelers are offered. The best known of these is the GIA Graduate Gemologist certificate program, as many independent jewelers complete the course to develop proficiency in identifying all the factors making up a diamond’s quality according to GIA standards.

AGS was started in 1934 and has since grown to approximately 3,400 jewelers and other companies related to the jewelry industry.  AGS began offering diamond grading services in 1996.

EGL has fewer locations than GIA, operating labs or offices in a few European and Asian metropolitan areas and, independently through the EGL-USA, select major American cities. Formerly two branches of one organization, the original EGL, and the EGL-USA ended their association and began operating as unaffiliated organizations in the early 1980s.

Which Lab is Right for Me?

Adiamor’s customers ultimately typically purchase GIA certified diamonds compared to AGS due to the larger GIA inventory.  Both GIA and AGS Laboratories have excellent records and multiple methods in place to ensure transparency and accountability in all processes, so which lab certification an individual chooses depends mainly on which diamonds fit their criterion.

While GIA offers similar services in the way of grading, certification, and security, GIA has a much longer history than AGS or EGL. GIA was the pioneering agency in many techniques, processes, and innovations that served to make all competing diamond labs what they are today.

Additionally, the GIA operates as a non-profit while the EGL is a for-profit organization. This is an important distinction for many diamond buyers as the GIA’s non-profit status adds another layer of accountability and makes objectivity on the part of the gemologist much more likely. The general acceptance of GIA’s quality standards as superior to other laboratories may even be a direct result of operating this way; the outcome of each non-profit lab certification is the same for the gemologist regardless of his or her findings, and without the possibility of kickbacks, there’s no incentive to exaggerate or overlook a diamond’s defining characteristics during the analysis.

If simply having a certification and report attached to an aesthetically pleasing diamond or saving money is your priority, the EGL may be the way to go. Without the same history and resources the GIA can offer, the cost of EGL certification is slightly lower and allows consumers to purchase a more affordable certified loose diamond. The downside to this is that obtaining insurance or an appraisal for the diamond consistent with the information given on the EGL report can be challenging as the more critical GIA, or AGS standard is widely preferred.

Selecting a Certified Diamond

If you’ve chosen which certification you prefer and wish to proceed selecting a diamond, or if you have additional questions about the benefits and drawbacks of choosing a diamond from a specific lab, contact Adiamor. Our certified diamond specialists can guide you through the selection process, answer more specific inquiries not addressed above, and match you to the perfect certified loose diamond for the jewelry you’ve selected.