QuestionQUESTION: Hi, I'm interested in a square-ish cushion cut diamond, about 1.5-1.6 cts, but am having a hard time figuring out what's considered a good cut since there seems to be no established consensus on that. I don't like the "crushed ice" look, so are there depth and table %s to stay stay away from to avoid that look? I recently considered a 1.57, 1.25 ratio (I find that too rectangular for my taste) with table 59% and depth 67.7%. I feel it's a a little bit "crushed ice" but otherwise can't tell how good this cut is (it doesn't look too different than other stones I saw). I see alot of diamonds online with these similar table and depth %s. The GIA doesn't give other measurements, so when a jeweler tells me that all these other numbers are important too, I feel quite lost. Can you give some guidance as to what to look for in a stone this size to get a nice clear symmetrical look that has depth to it when you look into the stone?
Also, I realize you're with GIA, but are other certifications reliable too? And do you think an IGI appraisal is necessary before I buy or will a jeweler's own appraisal do, for insurance purposes?
I realize it's a handful of questions; I greatly appreciate your response. Thanks.
ANSWER: Hi Rania,
Your confused because your looking for a premium stone in a bargain basement market. Thats why your not finding what you want.
To buy what you want you need to buy a Certified Diamond with a Very Good to Excellent Cut Grade. It needs to have an AGS or GIA Certificate. Nothing less.
Most diamonds that I see that are non certified or certified by IGI have lower cut grade proportions. Thats why most IGI Certificates have no provision for cut grade outside of Table % and Depth %.
Arthur DeMello GG (GIA)
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QUESTION: Thanks for the response Arthur, but that doesn't quite clear up all my confusion. Most stones I've seen are GIA but no where does it rate the cut grade. "Excellent" or "very good" only describe the symmetry and polish on GIA certs that I've seen. For GIA certified diamonds, can you guide me as to what proportions or other features to look for to find a stone that is considered an excellent or very good cut grade as you say? And how can I avoid that "crushed ice look"? Are there particular proportions or #s to avoid, or is it purely a visual thing?
ps. If I wanted to discuss this in person with you or the appropriate professional, can you advise on that? Many thanks.
AnswerMany of the GIA Certs have Cut Grade and some dont. If your jeweler is showing you Diamonds with GIA Certs that dont list cut grade you need to look for diamonds with GIA Certs that do with a different jeweler that specializes in Very Good to Excellent Cut Grade Diamonds.
If a diamond has a GIA Cert without a cut grade many times it was because the Jeweler bought the cert without the cut grade provision. Cut grade Certs from GIA are usualy done on diamonds that have very good to excellent proportions so that the GIA Cert can be used to show off the Well Cut Diamond and not to hide the entity as done in GIA Certs that do not include the cut grade feature. I recommend a 72% depth and 64 - 74% Table. Also a Crown Angle of 34 degrees and a pavillion angle of 41 degrees. Med - sl thick girdle edge.
This should eliminate the crushed Ice effect your talking about.
I am available for consultation by telephone or at any of my office locations.
Arthur DeMello GG (GIA)
http://www.nationalgemologicallaboratory.com
http://www.jewelryappraiser.info
