Obviously, you don't need to do this while looking at IF diamonds! A diamond with an IF grade is unquestionably eye-clean. However, in our opinion, it is quite improbable that an internally perfect diamond would have any faults that are severe enough to have a negative influence on brilliance. Occasionally, we hear individuals imply that the possibility for exterior flaws to have an impact upon light performance. Simply put, we cannot perceive this. Instead, when assessing crucial light performance, the focus should be on cut quality. The overall diamond cut's accuracy has the most influence on how much light the stone reflects and sparkles.