Optimal Measurements

Correctly measuring cut on a Radiant Cut diamond requires a new approach, because of the fundamental way in which rectangles, like Radiant Cuts, differ from circles, like round stones. A circle is a perfectly symmetrical shape; a rectangle is not. Thus, they must be measured in different ways.

Measuring a Round Stone versus a Radiant Cut

In general, a well-made diamond of any shape must have the correct overall depth relative to the size of the stone, a measurement referred to as "depth percentage." The depth percentage must also be properly distributed between the crown (top) and pavilion ("bottom") of the stone. These measurements are referred to as "crown height" and "pavilion depth."

In round diamonds, depth percentage, crown height and pavilion depth are measured relative to the diameter of the stone. This makes sense, because of the symmetry of the circular shape. All circles with the same diameter have the same surface area.

These measurements have been applied to other shapes, like Radiant Cuts, by simply substituting the width of the rectangle for the diameter of a circle. Laboratories like the Gemological Institute of America (the "GIA") continue to measure in this way.

A GIA diamond grading report will, for example, include a "depth percentage" calculated by dividing the depth of the stone by the width of the stone. Unfortunately, this analysis does not consider the length of the stone, resulting in an oversimplified measurement.

For example, a diamond measuring 5 millimeters in width by 7 millimeters in length has a far larger surface area than one which is also 5 millimeters in width, but only 5 millimeters in length. The first stone would have a 35-square millimeter surface area, and the second a 25-square millimeter surface area. Given the 10 square millimeter difference in the surface area, these two stones would need very different depths to maximize the beauty of each stone. By focusing only on width, traditional depth percentage calculations fail to account for this difference. RCDC has created its own measurement standards for our Original Radiant Cut Diamond to address this issue.

RCDC Measurements Consider Both Length and Width Measurements

At RCDC, we adjust our measurements of "depth percentage", "crown height" and "pavilion depth" to account for both the length and width of the stone. Our calculations ensure that our RCDC Original Radiant Cut Diamonds are properly proportioned with respect to all dimensions.

RCDC Ensures All Original Radiant Cuts Spread Their Carat Weight

Due to improper proportioning, many diamonds appear smaller than more finely cut stones of the same carat weight. Uneducated customers often pay more for ordinary stones which weigh more, when a lighter well cut stone will actually create a larger more beautiful piece of jewelry. Because this issue is so important, we scientifically measure the actual "spread" of each of our Original Radiant Cut Diamonds, even taking into account the area lost as a result of the cut corners. This measurement (geometrically the area of the girdle plane in square millimeters) allows us to ensure that our customers never pay for unnecessary carat weight that cannot be seen.

All RCDC Original Radiant Cut Diamonds meet the following tolerances, which have been determined by Henry Grossbard, inventor of the Radiant Cut Diamond, to be essential to a well-made Radiant Cut of that size. Each stone must meet both the traditional criteria and our more advanced criteria.

In addition, each Original Radiant Cut Diamond is visually examined to provide 100% assurance that its light performance meets the highest standard.

Choices can be made within these ranges to reflect personal preferences, but all Original Radiant Cut diamonds weighing in excess of .70 carats fall within these parameters. The vast majority of diamonds marketed as "Radiant Cuts" do not. Many jewelers, and even diamond dealers and manufacturers, are unfamiliar with the proper proportioning of the Radiant Cut. Only the RCDC Original Radiant Cut guarantees that your diamond is cut to these rigorous requirements.