The History of the Ideal Cut
For decades, the diamond industry has relied upon the work of Marcel Tolkowsky to set the standard for the optimal proportions that constitute a Traditional Round Brilliant Cut Diamond. Tolkowsky's exceptional work focused on determining the most desirable proportions for a Round Brilliant Cut with a specific 58-facet arrangement. It provided good applications of optics and mathematics to the design of the round diamond. Tolkowsky’s mathematical model was far more optically efficient than the Old Miner and Old European cut rounds. Since that time, many have associated his best proportions with being the Ideal Round Brilliant Cut diamond.
However, to qualify the term Ideal, a diamond must have the greatest degree of brilliance, fire, sparkle, and beauty that is possible for a round-shaped diamond. Tolkowsky’s cut does not fit this classification since he did not set out to determine the faceting arrangement that would result in the most brilliant and beautiful round diamond. Due to the technological limitations of his time, certain calculations were literally too cumbersome to do. His goal was to simply determine what proportions were optimal for the existing 58-facet model that was popular at the turn of the 21st Century. Nevertheless, his achievements are proof that the union of science and the art of faceting a diamond do lead to a better diamond. His work has inspired future generations to go down the same path of seeking the perfect geometric arrangement that leads to the most beautiful diamond possible. This brings up the larger question of whether there exists a superior faceting arrangement that is more optically efficient and beautiful than the traditional round brilliant cut model.
Tolkowsky’s Ideal Cut
In 1919 a young mathematician, Marcel Tolkowsky, developed the optimal proportions for round brilliant cut diamonds. Tolkowsky provided several sets of proportion measurements for what he believed to be the best-looking cut. This is the basis for the traditional model of what many in the industry call the "Ideal Cut” (Crown 34.5°, Pavilion 40.75° and Table 53% is one of five sets that's very popular and is currently considered "Ideal" by the American Gem Society.) However, even Tolkowsky understood that his measurements were just one opinion in a range of proportions for beautiful diamonds, and that a diamond's beauty was unique to each viewer. Thus, the beauty of a diamond is governed by scientific principles, but only an experienced diamond cutter can bring out the best in a diamond with his artistic abilities.
Tolkowsky’s Measurements Still Used Today
Mr. Tolkowsky provided specific mathematical tolerances for the crown angle, pavilion depth and table size of his ideal cut diamond. Even though Mr. Tolkowsky's analysis of the baroque brilliant diamond was empirical in nature and based on a two dimensional model with no emphasis on girdle thickness, amazingly, Mr. Tolkowsky's measurements are still today regarded by many in the diamond world as the standard for ideal proportions for a round brilliant cut.