Articles about Diamond Grading
To the naked eye a D Flawless diamond can appear identical to an F VS diamond if each has been cut the same way. Alternately, less than one degree of variation in two diamonds’ facet measurements can make a noticeable difference in appearance - yet both could be issued the same cut grade from a given lab.
Consumers’ Problems and a Solution
By Sergey Sivovolenko, Janak Mistry, Garry Holloway and Dr Yuri Shelementiev