BRILLIANT
The name given to a round cut diamond with 58 facets: 32 facets above the girdle, 24 facets below the girdle, plus the table (the large uppermost facet) and the culet (the facet at the tip of the diamond).
The “brilliant cut” is the most frequent choice for diamonds as it brings out the full luster and brilliance of the stone.
It is the result of extensive research into physics and optical phenomena applied to the diamond, and was perfected around 1920.