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Grading the Light Behavior of Ideal Cushion Cuts

Recently I had the opportunity to use a Verigem® device, an objective light behavior tool specifically created for diamond light return grading, to examine two Branded Cushion cut diamonds which happen to have the AGSL blessing of Ideal make.  These are diamonds designed and marketed by one of many popular vendors on Pricescope.  When you first see them you hardly can tell they are cushion cuts because their brilliancy makes your eye see what might be a round shape.  Upon closer inspection, of course, the rounded corners and flatter sides do show themselves to be present.  Like every other Ideal Cut which AGSL has developed cut grading standards for, these diamonds show all the design characteristics of finely cut diamonds.  And, sure enough, both a Hearts and Arrows effect are perfectly displayed with a viewer.

I have often stated that the occurrence of H&A is a happy accident, in that the two phenomena both work well with romance.  However, hearts and arrows, when perfectly formed, do confirm a great deal of time and effort has been spent on creating exacting symmetry in a diamond.

Although I do not have access to the database of diamonds at Imagem, Inc, ( the firm CEO, Dr. Aggarwal, assured me that the results of this limited test placed these diamonds in the top 20% of the “Excellent” cut grade scale.  Since thousands of diamonds are in this database, the comparison is on firm footing between the objectivity of the Imagem technical process for light behavior and the consistency of the AGSL techniques of measurement and assessment of cut quality. There are several other competing high performance cushion cuts in the market which have not yet crossed my desk or been put into a Verigem® light measuring device, but the availability of rather poor cut quality cushion shaped diamonds is far more commonplace.  Ideal, cut cushion diamonds which are finely cut, perform excellently with light and have consistency, let alone the blessing of AGSL techniques are quite rare at this time, but the market potential for such beautiful diamonds will encourage more production.  An Ideal variety of cushion cuts competes very favorably with round diamonds.  They are likely among the highest performing of all diamond shapes, and have increased weight retention from their rough crystal which makes for a somewhat lower cost per carat.  I’d think a cushion shape with a modified round brilliant facet design will allow a maximization of light return unlike other square outline fancy shaped diamonds.

Any vendors interested in testing their cushion cut stones would be most welcome and the results will be shared with you alone.  I will not make comparisons of one brand to another since the samples are not random and too small.  Fairness and knowledge is the highest goal.


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