Tolkowsky Ideal     Tolkowsky Ideal Proporitons   In 1919 a young mathematician, Marcel Tolkowsky, wrote a Masters thesis on the proportions for round brilliant cut diamonds. This is the basis for what we now call the "Ideal Cut". It is said he began his study by showing passers by in the streets of London a selection of diamonds. This way he learned the proportions of the diamonds that looked the best. The diamond cutters in his family's business also influenced his preferences. I believe he then used mathematics and physics to prove why they were preferred. The basis of Physics is observe, theorize and prove and so his standard has stood the test of time, in spite of the mistakes in the thesis as pointed out by learned commentators such as Dr Ilene Reinitz from the GIA. But Tolkowsky unwittingly had a negative impact on the diamond industry by providing a single target (Crown 34.5°, Pavilion 40.75° and table 53%) that became the basis for brilliant cut diamond proportions. Had he not chosen well, it would not have taken 80 years to improve on his work. Tolkowsky was aware of the trade off between two of the keys to diamond beauty - brilliance and dispersion. He knew a range of proportions of beautiful diamonds and that beauty is to some extent in the eye of the beholder. But Tolkowsky never intended cut grading scales on simplistic and convenient tolerances applied to his optimum proportions. Naturally cutters produce the heaviest (and worst looking) diamonds that fit these tolerances.