The oval brilliant cut first came out in the year 1957. Its design is credited to Lazare Kaplan, who is one of the most famous people in the diamond industry. Kaplan founded Lazare Kaplan International, which carries the patents for the laser inscription process used on diamonds as well as for the HPHT method. Lazare Kaplan is also related to Marcel Tolkowsky, the man who found out the ideal proportions for the modern round brilliant.
Oval Brilliant vs. Round Brilliant
With an elongated shape, the oval has steeper angles at the belly than at the ends. For this reason, light performance cannot be optimized across the entire oval. This means the performance of the round brilliant cut is better in terms of light output.
Where rough yield is concerned, oval diamonds are only cut out of rough stone that is suitable for nothing else. When used in fancy stones, the size of the finished stone is considered paramount, and dictates the height of the shoulders. So, the rough yield will be more for an oval brilliant than a round brilliant. In addition, the price per carat of the oval brilliant is somewhat less than that of a round brilliant cut diamond engagement ring.