Diamonds - Version 2.5 The Round, or Brilliant Cut Diamond is, by far, themost popular shape for diamond engagement rings. It iscone-shaped to maximize light return through the top ofthe diamond. It is cut to have 58 facet - 33 on thecrown and 25 on the pavilion. The relationship betweenthe angle of the crown (above the girdle) and thepavilion (below the girdle) is complementary. A steepcrown angle is complemented by a shallower pavilionangle & vice versa.