There are A LOT of independent laboratories that certify diamonds, and it can get quite confusing trying to sort them all out (so many acronyms to remember)!
When we decide to get a diamond certified at Gray & Davis, we use either GIA or EGL. Here’s why:
Back in the day, there was no standardized terminology for evaluating diamond quality. A diamond dealer could use whatever descriptors they wanted to convince a consumer that a diamond was of high value. When the Gemological Institute of America (GIA) was founded in 1931, they wanted to give consumers a way to truly understand the quality of the diamond they were purchasing. To this end, GIA introduced the D-Z color scale and Flawless – I3 clarity scale. These grading scales became a huge hit, and are now part of the universal language of diamonds. Now, when customers and dealers are looking at a whole bunch of diamonds, they can reference lab certificates to make sure they’re comparing apples to apples. GIA lab reports are the standard against which other lab reports are judged. They are known to be incredibly strict with their grades, i.e. a diamond that receives an “L” color from GIA may receive a “J” or “K” color from a different lab. For large, high quality diamonds, GIA is our go-to lab.
BUT, there are some drawbacks to GIA that make it difficult to us to use them for every diamond that crosses our path.
1) Because GIA receives sooo many diamonds from sooo many huge companies to grade every day, there is currently about a 6 week turnaround to certify a diamond. As you can imagine, this can be a bit impractical when we have a client that needs to work within a certain time frame.
2) GIA will not certify diamonds that are already set in a piece of jewelry. This is because settings make it impossible to view a stone from all angles, so certain tiny inclusions can remain hidden from the diamond grader. This is certainly solid reasoning, but because at Gray & Davis we work with antiques, removing the stone for certification and resetting could mean damaging original piece.
Enter EGL USA:
The EGL USA, or European Gemological Laboratory of the United States of America (good name, yes?), offers some solutions to these problems while still providing a fair assessment of a diamond’s quality. First and foremost, they WILL give reports for diamonds that are already set, which means we don’t have to dismantle our lovely antiques just to get a diamond certificate. To account for the interrupted visibility of grading a mounted diamond, EGL will never give a set diamond a clarity grade higher than VS1, and they often assign a diamond a color range (so you might see the color listed as J-K on the report). Their turn-around time for reports is a few days, not a few weeks, which makes them much more practical when there is a time crunch.
You may have heard that EGL USA tends to give stones a higher grade than they would have gotten at GIA, and you would be right. However, because this fact is common industry knowledge, EGL graded stones are sold at a discount compared to their GIA counterparts to account for any grading discrepancies. For example, if you are buying a stone that received an I color, SI1 clarity from EGL, you might expect to pay the same price as if you were purchasing a J color, SI2 clarity diamond from GIA.
Because most of our antique and vintage pieces pre-date the existence of official gemological laboratories, we carry many diamonds that were never certified at all! This is why we are always happy to provide an appraisal that clearly states the opinion of our GIA trained staff gemologists. The appraisal is our business’s guarantee that the piece we sold you is of the age, quality and materials stated.
A diamond certificate can be an important document to help you feel secure about your purchase. GIA certainly set the standard, but when searching for the perfect antique or vintage diamond, keeping an open mind about lab certificates can unlock whole other worlds of options.