Diamond Information Pavillion
The Pavillion is the section from the girdle to the culet.There are 2 measurements to consider when looking at the pavillion. Firstly, the pavillion depth which is the measurement from the girdle to the culet given as a percentage of the overall depth. Secondly , the pavillion angle which is the angle made between the girdle and the culet. The Accredited Gem Appraisers (AGA) state that for a round brilliant cut the pavillion depth percentage must be between 42.8% and 43.2% for a perfect Ideal cut.The AGA do not specify an ideal pavillion angle but it is widely accepted that the ideal pavillion angle of 40.75° corresponds to a pavillion depth percentage of approximately 43%.
Marcel Tolkowsky was a pioneer in the world of diamonds, and was the first person to present a mathematical analysis of diamond cut. In 1919 he released the 'Diamond Design' , A study of the reflection and refraction of light in a diamond. He concluded that a diamond , having the most perfect fire and brilliance should have a single set of proportions. A diamond with no culet and an extremely thin girdle should have a 53% table, crown angle 34.5° , crown height 16.2% , pavillion angle 40.75° , pavillion depth 43.1% and an overall total depth of 59.3% . One must remember though that Tolkowsky's set of proportions will be different for any diamond that has a culet or a thicker girdle
