The most popular diamond jewelry shape has been the round brilliant because people believed it to be an "ideal cut" that displayed the most brilliance and sparkle in a Tiffany Style Diamond.
Usually the wedding rings rough will be cut into whichever shape that requires the least amount of sacrifice. Marquise and oval shapes should have a length thats exactly twice the size of the width. If they are too narrow or too wide, the stone will loose light and appear too dark.
For centuries, men and women have found that the sparkle and brilliance of a quality diamond dealers expresses their deepest emotions and symbolizes their enduring love.