I love that I am starting to get some really excellent questions on the blog that I can sink my teeth into. If you didn’t know, I am a certified gemologist with the GIA. This means that I have had extensive training to grade diamonds and colored stones. I have also been in business for over 30 years, which means that what I lack for in education, I make for in experience.
This also means that you can ask me questions anytime and I will always answer them, because I want you to be able to buy the best diamonds you can. Today we have a question form Laura about a cushion modified brilliant diamond that she bought.
Laura asked…
I have been trying to get an answer to a question about a Cushion Modified Brilliant diamond I just purchased. This Cushion Modified Brilliant diamond was already set in a very beautiful setting and I came across it by accident. I asked the jeweler about the ring and he told me it was a GIA certified 1.00 ct, F color, si1, radiant cut. My original engagement ring was recently stolen and I was looking for a replacement. I went back and asked to see the GIA cert. He could not find it, it said he had the diamond for a while and then had it set. He took out the diamond and sent it back to GIA. In about three weeks he called me to tell me the cert came back. It now came back as a cushion modified brilliant, 1.00 ct, color E, good symmetry, very good polish, no flor, no cutlet, girdle was very thin -ext thick. The table was 71% and depth 6 9.4%. Everywhere I look it says the table should be smaller. The diamond is very rectangular and has a 1.26 L x W ratio. I personally love it but in certain lights it looks flat in others it looks wonderful. The plot is not the crushed ice plot but the one that the facets go all the way to the end, The X factor type. Can you tell me what the cut grade could be?
The Cushion Modified Brilliant
In a previous blog, I mentioned that there is no cut grade on a fancy shaped (non-round) diamond, so any attempt to analyze the cut of the diamond without seeing it would be pure conjecture on my part, so let’s get that out of the way first.
It is awesome that the jeweler gave you a Cushion Modified Brilliant diamond that was better than what he represented it to be. This happens fairly often with us but only in the case where the diamond was not certified to begin with as opposed to your case where the jeweler lost the previous certificate. I assume your Cushion Modified Brilliant does not have strong or very strong fluorescence, which once in a while can make the diamond look a bit milky.
The 71% table is a bit big for my taste and could be a slight factor in making your diamond look flat, as could the slightly deeper depth. Also, the ratio of the top (crown) to bottom (pavilion) could affect the way the diamond looks. By flat, I assume you mean not as brilliant looking as opposed to saying the top facet of the diamond literally looks flat like a desktop.
A couple of other possibilities could be that incandescent light makes a diamond sparkle differently than florescent lights. Does your diamond sparkle more in sunlight than under the florescent lights in your office? That would be normal and have nothing to do with the diamond itself. Are you keeping the underside of the diamond clean? When the underside of a diamond gets gummed up with soap it loses its sparkle.
I would test your diamond this way. Put 3/4 cup of water in your microwave for 15 seconds until it is warm but not real hot. Add 1/4 cup of plain old generic household ammonia. Scrub the underside of your diamond for several minutes with a toothbrush and the ammonia and water solution. If you can still see soap scum on the underside of the diamond, let it sit in the warm water for 20 minutes and then scrub again. Rinse it off in tap water the same temperature so the ammonia is removed, and take it outside in the sunlight and see what you think of the sparkle.
If you are still bothered by how it looks, you probably need to discuss your concerns with the jeweler you bought it from. If you are not getting an answer that you respect, you can try making an appointment with a totally independent gemologist (not affiliated with any jewelry store) for a 2nd opinion. If you are not personally familiar with a good gemologist look for a certified gemologist (GIA pedigree), Certified Gemologist Appraiser (even better degree) or a gemologist that is a member of the American Society of Appraisers. If you tell me what city you live in, I may be able to suggest a name for you, but you really should first listen to what the jeweler you bought it from has to say, as he may have an explanation that satisfies you, other Cushion Modified Brilliant diamonds to compare it to just to satisfy your curiosity, or even a replacement diamond that makes you happier!
