The round diamond, developed by Marcel Tolkowsky in 1919 as the ideal diamond cut, is the most traditionally sought after diamond cut for engagement rings. It accounts for 75% of those sales, as well as those of other jewelry.
Coming from seven generations of diamond jewelry makers, Tolkowsky asked individuals on the street to identify their ideal diamond cut out of a selection of diamonds. He then used these results to create the ideal diamond cut, using percentages and angles. He put together the first ever mathematical formula for cutting the perfect diamond and used this theory as the premise for his Master’s thesis. His standards for an ideal diamond cut last to this day, with only a few minor changes. The ideal diamond cut is split into two major categories: the American Ideal diamond cut and the Eppler diamond cut, the latter of which is popular in most European areas.
A round diamond cut has 58 facets, which determine light exposure and how it is refracted off the jewelry so that it will sparkle outwards. The facets on a round diamond are usually shaped like triangles or kites; the most important being the table facet located on the top of the diamond, which should be an octagon shape.
The round diamond cut is the most flexible in terms of radiance, brilliance, inclusion or exclusion of accents, and the type of setting it is placed in, as well as the four C’s of diamonds: cut, color, clarity, and carat. While originally popular for engagement rings, the round can go into any type of jewelry easily, such as an eternity ring, which has stones surrounding the entire band. The popularity of round cut diamond jewelry also makes it the most expensive of all the diamond cuts.
A famous example of a round diamond cut is the 84.37-carat Chloe diamond, which was auctioned off at Sotheby’s in 2007 to Georges Marciano for $16.2 million. This was the largest brilliant round diamond cut to ever be auctioned and took two years to cut. Another famous example is the Dresden Yellow, a 38-carat diamond.