The 4 Cs are the most important major aspects influencing diamond value and quality. However there are more smaller but vital intricacies which go a long way to affect the brilliance of the stone. Depth of the diamond is one such factor. Depth refers to the height of the diamond from the table top facet to the culet bottom facet. How good would be the brilliance of the diamond, depends on the accurate depth of the diamond. A shallow cut or deep cut diamond allows the light to escape killing its brilliance.
The depth of the diamond to a great extent decides how the numerous facets of the diamond will positioned during the cutting process. These facet angles play a crucial role in giving brilliance to the diamond. The depth of the stone varies with the cuts.
So if you really want to reveal the mystery of the sparkling, mesmerizing diamond aura then jump into its depth, literally.
Depth percentage is the proportion of the total diamond depth as compared to the total diameter. Depth percentage affects how the light will interact in the diamond, and thus impacts its brilliance. It is calculated by dividing the total depth of the diamond by the total girdle diameter. The total diameter is fixed to 100% as a rule for all diamonds. However while calculating depth percentage the dimensions in millimeter are considered later multiplied by hundred for percentage value.
Depth Percentage Fancy Cut Diamond = depth (in mm)
total width (in mm)
A round brilliant diamond has a different criterion to calculate the depth percentage. Here the total depth is divided by the average girdle diameter. For example, if the average diameter is 6.00 mm and total depth 4.00 mm the depth percentage will be 66.7%.
Depth Percentage Brilliant Cut Round Diamond = depth (in mm)
average girdle diameter (in mm)
The Depth Percentages that are commonly considered best for each shape may vary slightly. As exceptions princess, radiant and emerald cuts, can have 70 - 75% for acceptable depth percentage range. To have better understanding refer to the Depth
Percentage chart below:-