A diamond intersect constitutes a another or less symmetrical arrangement of facets which cool change the shape and appearance of a diamond crystal. Diamond cutters must excogitate diverse factors, such as the shape and extent of the crystal, when choosing a cut. The practical story of diamond cuts can be traced back to the Centre Ages, while their notional justification was not developed until the turn of the 20th century. Base creation and innovation advance to the coeval day: current technology-notably laser cutting and computer-aided design-has enabled the adding to of cuts whose complexity, optical performance, and misuse lessening were hitherto unthinkable.

The most usual of diamond cuts is the current round brilliant, whose feature arrangements and dimensions bear been perfected by both mathematical and empirical analysis. Further common are the fancy cuts which come in a assortment of shapes-many of which were derived from the round brilliant. A diamond's section is evaluated by trained graders, with higher grades obsessed to stones whose symmetry and magnitude most closely match the specific "ideal" used as a benchmark. The strictest standards are applied to the round brilliant; although its plane count is invariable, its immensity are not.

The Allnatt Diamond, a blimp Fancy Bright Low diamond
The Agra Diamond
The Amsterdam Diamond, a 33.74 karat (6.748 g) nigrous diamond which sold for $352,000 in 2001
The Archduke Joseph Diamond
The Ashberg Diamond
The Briolette of India Diamond
The Centenary Diamond, the world's largest colourless (grade D), flawless diamond
The Chloe Diamond, the largest top-quality, brilliant-cut achromic diamond ever to arrive at auction, bought for blameless under $16.2 million and named by Georges Marciano, founder of Guess Jeans.
The Cullinan Diamond, the largest rugged gem-quality diamond ever fashion at 3106.75 carats (621.35 g). It was divide into 105 diamonds including the Cullinan I or the Enormous Star of Africa, 530.2 carats (106.04 g), and the Cullinan II or the Lesser Star of Africa, 317.4 carats (63.48 g). (Feature of the British Coronet Jewels Imperial Society Crown)