The Mirror cut is characterized by an extraordinarily large table and thick girdle consisting of as much as 90% of the width of the gem. This makes the gem highly refractive and literally gives it the properties of a mirror, hence the name.
Sometimes referred to as the “Thin Stone”, the Mirror cut was an early 16th century phenomenon that is making a comeback. It is a variety of the Round cut and appears in the names of some historic Diamonds including the “Mirror of Portugal” and the “Mirror of France”.