The length to width ratio of a emerald cut diamond is important to its value. Popular diamond quality reports from GIA and other gemological laboratories do not provide length to width ratios. However, they do provide  length, width, and depth measurements. Length to width ratios are determined by dividing the length measurement by the width measurement. Measurements are always calculated to the one-hundred of a millimeter. (Example) Emerald length equals 6 millimeters. Emerald width equals 6 millimeters; 4 millimeters divided by 6 millimeters equals a length to width ratio of 1.5 to 1

The best emerald cut diamonds will have a length to width ratios between 1.35 to 1 and 1.65 to 1. Length to width ratios within these ranges are preferred. A emerald cut diamond's length to width ratio is largely determined by the original size of the rough diamond crystal. When a rare fine quality diamond is cut by an experienced diamond cutter, the weight and value will never be sacrificed simply to make a diamonds length to width ratio 1.50 to 1. If the diamond is within the range of 1.35 to 1 and 1.65 to 1, extra weight is usually not removed. Take this time to return to our list of certified diamonds and choose the perfect emerald cut diamond that is as affordable and beautifully shaped.