Crown Height Round Brilliant Cut:

Crown height percentage is calculated by dividing the actual height of the crown by the average diameter. Measurements are rounded to the nearest .01 millimeters. The crown is the height of the diamond from the girdle edge to the surface of the table facet. Crown height can effect both the dispersion and brilliance of a diamond.

The AGS Ideal 0 Cut grade includes a narrow range of crown height from 15 percent to 16.2 percent.

Diamonds with ideal to very fine cut proportions have a crown height between the ranges of 13.1 and 16.2 percent. It is difficult to visually recognize differences in the appearance of diamonds that have crown height within the range of ideal to very fine.

Diamonds that have crown height percentages that are lower than 13 percent often have larger tables. This often produces less brilliance and less dispersion and fire. In contrast crown heights that are greater than 16.2% give the diamond a lumpy, top-heavy appearance, and disrupt the balance of fire and brilliance.

If you have any more questions concerning crown angles or proper cut proportion, contact our Certified Gemologist-Appraisers toll free at 1-800-766-7119.