A marquise diamond ring is cut in an elongated, oval shape that is tapered and features sharp tips at the ends of the oval with the width to length ratio of the oval usually between 1.5 and 1.75. This means that the oval shape can be quite narrow or thick. Marquise diamonds are a variation of the round brilliant cut diamond shape and have a total of 58 facets which provides them with their particular sparkle.
This diamond cut was created in the 17th century on the instructions of King Louis 15 of France who wanted a stone that mimicked the shape of the lips of the Marquise of Pompadour who was his mistress at the time – hence the origin of the name. This cut is also sometimes called the navette (‘little boat’ in French) or the lemon cut.