
Diamond Anatomy
All the individual structural features of a diamond determines the proportions of the diamond and in turn, affects the appearance and light performance of the diamond. While each feature matters, the overall appearance and cut quality of the diamond is based on the combination and interactions of all the features.
(Mouse over the options below to learn more about each feature.)
Table
The table is the flat surface at the top of a diamond. It is the largest facet of a diamond.Light enters the diamond through the table of a diamond and is reflected back up from the pavilion through the table. The brightness seen from a diamond is the result of the light that reflects through the table of the diamond.
The size of the table affects the amount light that can enter and exit the diamond and is therefore an important factor that gemologist use when assigning the Cut grade.
Crown
The crown encompasses everything that is above the girdle.Light refracted through the crown and reflected back from the pavilion into the observer’s eyes.
The light is disperse in different directions due to the various facets that are on the crown and that is what creates the stunning colour fire that can be seen.
Girdle
The girdle is the widest part of a diamond and is between the crown and pavilion.The GIA number assigned to a diamond is laser inscribed on the girdle of the diamond and is only visible through magnification with special equipment.
Pavilion
The pavilion is the area that is below the girdle of the diamond and the bulk of a diamond’s weight is typically held in the pavilion.Pavilion angles that are either too deep or too shallow will allow more light to escape from the side or bottom of the diamond and therefore affects the cut grade of the diamond.
Culet
The culet is the facet at the tip of the diamond.Diamonds that have small culets exhibits more brilliance as a large culet allows more light to escape through the bottom of the diamond.
Depth Percentage
The depth percentage is the ratio of the depth against the diameter of the diamond.The depth percentage is one of the key factors in determining the cut grade of a diamond.
To optimise the sparkle of a diamond, the depth percentage should be between 54% to 66%.
Table Percentage
The table percentage is the ratio of the table size over the diameter of the diamond.The table percentage is the measure of the balance between the table size and the diameter of a diamond.
A table percentage that is too high or too low will result in the top of the diamond looking too flat or rounded which will lower the sparkle of the diamond. The ideal table percentage is between 53% to 70%.
Crown Angle
The crown angle is the angle between the crown and the girdle.Diamonds with optimal angles will yield more sparkle.
Crown angles that are too large or too small will limit the sparkle of the diamond as it affects how light reflects through the diamond. The ideal crown angles fall between 33.7% to 35.8%.
Pavilion Angle
The pavilion angle is the angle between the pavilion and the girdle.Diamonds with optimal angles will yield more sparkle.
Similarly with crown angles, pavilion angles that are too large or too small will limit the sparkle of the diamond as it affects how light reflects through the diamond. The ideal pavilion angles fall between 42.5% to 43.5%.