Culet is a term used to describe the small facet at the bottom of a diamond. It is a flat, smooth facet cut into the pavilion of the diamond and is used to protect the point of the diamond from chipping or breaking. The culet is typically very small, only a few millimeters in size, and is usually invisible to the naked eye. It is an important factor to consider when evaluating the cut of a diamond, as the more precisely cut the culet, the better the protection it provides.
