Also known as the “Single Cut”, an eight cut is a variation of the brilliant cut and is often used on Diamonds under .05ct. Despite its name, it actually has 17 or 18 facets (depending on if a culet facet has been added).
On the crown, there are 8 facets plus the table, and below the girdle there are a further 8 facets on the pavilion. As with a round brilliant cut, the pavilion is slightly deeper than the crown.
The eight cut, or single cut, is applied to very small gems where it is impossible to apply more facets. Furthermore, when gems are set on solid backgrounds (such as watch faces or certain cufflink designs), if no light is able to enter from the back, then the eight cut is normally applied.
Also, on the odd occasion when translucent or opaque gemstones are faceted into round shapes, they are often eight cut rather than round brilliant cut.
