The "over-grading" of diamonds is an issue that the jewelry industry has been struggling to resolve; More specifically, "using G.I.A. terminology while applying non-G.I.A. standards" (Rapaport March 2016) is happening way too often.
Until recently, Medlars has been happy to offer a number of different independent laboratory grading reports with our diamonds. However, it has become clear to us that a number of independent grading laboratories have become more than willing to intentionally "over-grade" in exchange for a diamond cutter's business. It has become common for us to see diamonds over-graded by 2 colors, 2 clarity grades and at least 1 cut grade. This allows less ethical jewelers to offer a specific grade at an apparent substantial discount compared to their competitors. In fact, there is a national jewelry chain whose business model is based on using these unethical laboratories to support their claim of the "lowest diamond prices".
The grade of a diamond includes 3 specific areas: clarity, color and cut. While not as critical in small stones (under 1/4ct.), the importance of accurate grading increases logarithmically as the size of the diamond increases. Let's use the example of a 1 carat round diamond: If it is graded SI-1 clarity and H color with a "Very Good" cut, our selling price, based on the Rapaport industry standard diamond pricing sheets, is $6,500.00. BUT if the diamond is one grade higher, such as VS-2 in clarity and G in color with the same cut, the price is $7,900.00.
Just as important, is the cut grade. A cut that's considered ”Good" would be reduced from the Rapaport price by 10%. If the cut is considered "Fair" the Rapaport price is reduced by 15%. The reason for the cut-grade discount? "Good" or "Fair" diamonds have to be re-cut to compete in brilliance with a "Very Good" or "Excellent" cut diamond. And, having a diamond re-cut will result in a re-cutting fee and a smaller diamond.
So, the question is, what can you do to make sure you get what you are paying for? Until the industry has a solution, my suggestion is to limit your choice of independent grading laboratories to G.I.A. (Gemological Institute of America) and A.G.S. (American Gemological Society). The Rapaport industry standard diamond pricing sheets are based on a G.I.A. cut grade of "Very Good" or "Excellent" and a A.G.S. cut of 00 or 000. Based on that information you can then determine who's offering you the best value.
These are my personal opinions and are only to be taken as such. “In free countries, every man is entitled to express his opinions and every other man is entitled not to listen.” — G. Norman Collie
Rapaport, M. (2016, March). Rapaport Calls For Standardization of Diamond Grading Terminology. Rapaport, 39(3), 34-35.
Posted by Chapman Stout on 10th August, 2016 | Trackbacks Tags: