DIAMOND ANATOMY GUIDE

DIAMOND ANATOMY

Every diamond, no matter its shape or size, shares a basic structure. However, each individual diamond will have its own distinct set of properties and proportions that defines its anatomy:

The upper portion of a diamond is considered the stone’s crown and measures from the top edge of the girdle (the edge of where the crown and pavilion meet) to the table (the largest polished facet on the top of the diamond). You can think of the crown and its facets as windows that allow light to enter the diamond and give it its brightness.

A culet is a small facet at the bottom of a diamond and is what helps prevent chipping and abrasion on the diamond’s bottom point. An optimally sized culet will not be visible to the eye. That is because large culets that are visible to the eye allow light to escape from the bottom of the diamond, rather than reflecting back through the top.

The depth of a diamond (or its height) is measured from the table at the top to the culet at the bottom. A diamond’s depth percentage, which impacts how light reflects off the facets in the stone, is determined by dividing depth by width. An ideal depth will vary depending on a diamond’s shape.

A diamond’s diameter, which is another form of measurement that can impact sparkle, is the width of a polished stone measured from edge to edge.

The girdle is where the crown and pavilion (the underside of a diamond) meet. A girdle should not be too thin, which can heighten the chance of chipping, or too thick, which can make a diamond appear smaller. A diamond with variations in its girdle thickness is considered to have symmetry issues and poor cut.

The pavilion is the bottom half, or underside, of a diamond. A pavilion’s facets, and the way light bounces through them, gives a diamond its brilliance.

A diamond’s table is the large, flat facet that you see when you look at the stone from above. Because this is the largest facet of a diamond, it is key to how brilliant a diamond will appear.