Most diamonds are cut for weight retention, which often results in a deviation from  "good proportions".  Often, the Diamond Cutter will sacrifice some of the beauty of the stone by cutting for a minimum of weight loss from the rough, which usually deviates from ideal proportions, but gets a larger finished stone.  The truth is that less than 5% of all diamonds are cut to ideal proportions.

Care must be taken to avoid buying a stone that has been cut too far  from the "excellent" proportions.  When a stone has either a very shallow or very deep cut, light is lost through the sides and bottom of the stone (pavilion), reducing its brilliance.  Since cutting a stone that has the "very good to good" cut or proportions usually results in a smaller carat weight stone.

Special notes on the term … Ideal Cut

The term "Ideal cut" is used to describe a range of dimensional tolerances that produce exceptional quality diamonds in terms of brilliance and dispersion. The term "Ideal Cut" does not intimate a single set of dimensions.

Care should be taken of the loose use of the term “Ideal Cut” as there is no universally accepted standard. There is some overlap in the dimensional criteria used by the recognized laboratories  to establish a grade of "Excellent to Very Good”. The major internationally recognized laboratories, HRD, GIA, EGL and IGI each grade cut as deviations from one of several standards and always within a range of tolerances, 

It is highly unlikely that there will ever be a single set of dimensions that will be universally accepted as the "Ideal Cut" as there is a relatively large range of dimensional possibilities that produce exceptional diamonds.

ICE Brand diamonds are selected from a range of tolerances that are included in both American and European standards with a special emphasis on visual beauty.

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