Your question assumes that the 'biggest' diamond is cut into a round cut, which may not be the case.
Most large diamonds are graded according to the carat weight when describing 'biggest', 'largest' and so forth: the largest raw diamond of gemstone quality ever found weighing more than 3,000 carats.
Larger diamonds weighing more than 100 carats are rarely cut into round brilliant cuts, so as to preserve the high carat weight of the diamond. You can review the list, below, to determine the characteristics of important diamonds.
me its 5in diameter
Mother Nature made the world's biggest diamond.
Using the query 'diameter' assumes that the diamond is a round brilliant cut. A 2.50 carat round brilliant cut measures about 9MM at the girdle -- your diamond's diameter will be slightly shorter.
It is the circle's diameter that is the biggest chord.
The biggest carat in a cut diamond is 20 carats. The largest diamond ever found was 530 carats.
The largest carat diamond ever is the Cullinan Diamond. This diamond weights in at 3106.75 carats which is around 1.37 pounds. The biggest diamond ring however, is 150 carats.
2527 diameters
it depends on the asteriod. asteroids are small and typically 10 meters in diameter. the biggest one is 974 meters in diameter
Ceres-about 1200 km in diameter
The biggest diamond in the world is the Cullinan diamond, which was found in South Africa in 1905. It is the largest gem-quality rough diamond ever discovered, weighing about 3,106 carats.
Building the Biggest - 2006 Diamond Hunters was released on: USA: 17 May 2006
The biggest diamond ring ever made is called The Spirit of de Grisogono. It weighs 312.24 carats, or 62.45 g. It is also a black diamond and is the largest black diamond ever found.