Better understanding the role of LGF

[steppapajon]

I am hoping that someone can point me to information on the effects of the lower girdle facets and how they contribute or subtract from the overall performance of a round diamond. I am looking for something more technical as the science of diamond cutting is intriguing to me.
SPJ

 

[Karl_K]

start here:
https://www.pricescope.com/journal/do_pavilion_mains_drive_light_return_modern_round_brilliant

Asked mods to move to RT.