Usually the fancy diamonds 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.
Most diamond wedding ring were formed more than 100 miles below the surface of the Earth, some from perhaps 400 miles down.
Most Tiffany Style Diamonds were formed more than 100 miles below the surface of the Earth, some from perhaps 400 miles down.