Round Cut Diamond

Description of Round Cut Diamonds

The round cut diamond is considered the standard for brilliance, even often called the brilliant-round cut diamond. It regularly contains a culet plus 57 facets (8 pavilion main, 16 lower girdle, 16 upper girdle, 8 star, 8 bezel, and the tabletop facet). However, some jewelers divide some of the facets to add even more sparkle to the diamond.

Round cuts are expensive to produce, removing more of the rough diamond than most other cuts.

History of Round Cut Diamonds

The first round brilliant diamonds were called Mazarin cuts, after the 17th century Ambassador Julian Cardinal Mazarin, who shaped a diamond to have 17 flat facets. Later, Vincent Peruzzi introduced 33 facets. Most notable, though, was Marcel Tolkowsky’s mathematical model to produce a 58-facet cut and maximize the brilliance with the perfect proportions of crown, diameter, and base. He published his findings in 1919 in his book, Diamond Design. Tolkowsky’s ideal cut included a diameter between 52.4% and 57.5%, a crown angled within the range of 33.7% and 35.8%, and a pavilion with measurement 42.2% to 43.8%. Other jewelers have declared different ratios to provide better sparkle. Math can help guide the purchase, but in the end, sparkle really is in the eye of the individual beholder.

Celebrities Wearing Round Cut Diamond Rings

Nicollette Sheridan (1.15-carat, H color, VS1 clarity, engagement ring returned to Nick Soderblom) and Pamela Anderson (4-carat engagement ring).

Trivia for Round Cut Diamonds

  • Over 75% of the diamonds sold in the past decade were round cut.
  • The De Young Red, a 5-carat red diamond, is housed in the Smithsonian Museum in Washington, DC. The crown’s main kite-shaped facets were divided in two horizontally to add yet more brilliance than a regular 58-facet round diamond.