The oval cut falls under the category of diamond cuts termed ‘brilliant cuts’ because the cut is designed to maximize brilliance. An excellent cut will produce a beautiful stone with superb brilliance and fire. However, achieving a good cut in an oval diamond is often unattainable. The stone has a complex and unique structure that requires superhuman precision to meet the precise standard parameters for an excellent cut. Given this difficulty, the cut quality should be determined by what you can see- sparkle, fire, and clarity. Watch out for the bowtie effect caused by the uneven light distribution- magnified by a too-shallow cut and absent in a too-deep cut. The bowtie is a dark shape that stretches across the center of the crown. The effect is glaring in some stones and barely visible in others. An oval diamond cut well will have a tiny bowtie or none. Use James Allen's 3D Video Technology with 40X Magnification to assess the diamond for large bowtie effects before buying it.
Ideal Length to Width Ratio of 1.45
The lack of a bow tie effect in the cushion cut gives it a leg over oval cut diamonds. Cushion cut diamonds come in various variations, but the cushion brilliant shines brightest. Its exceptional sparkle and fire are attributed to clear faceting and even better light dispersion. When observed from the top, a crisp, clear pattern is visible. It also has a larger face-up appearance because of the lower depth percentage. Admittedly, the cushion brilliant variation costs more, but its fiery brilliance makes it worth every extra buck.