Go for Ideal Cut Proportions as determined by either the AGS Laboratory or by Sarin DiaMension Computerized Proportions Analysis with Polish and Symmetry ratings of AGS Ideal [ID] or GIA Excellent [EX] with a color between 'D' and 'G' for "no brainer" white and 'H' to 'I' to max out the size and the diamond will still face up white when set in white gold or platinum prongs. Most people are able to see color easily in diamonds that are J color and lower (L/M/N and so on...) because the tonal value of the diamond will appear "warmer" than diamonds in the D to I color range. There is no right and wrong when it comes to selecting a diamond color, it is just a matter of personal preference that is probably best considered in terms of an absence of color, some people prefer diamonds which are cooler in appearance and some people prefer diamonds which are warmer in hue and thus we suggest visiting a local jewelry store to compare diamonds of different colors to determine your personal preference for color. The reality is that diamond color has no effect on the actual visual performance of a diamond.

We feel that "AGS Ideal" and "GIA Excellent" with ideal cut proportions as verified by Sarin proportions analysis are essentially the same "highest grade possible" from the two laboratories since they seem to grade essentially the same (high standards and ethics with a knack for consistency). Although there are a myriad of combinations of angles and degrees which will produce optimal light return in a round brilliant ideal cut diamond, you can narrow the field of possibilities and dramatically improve your chances of successfully selecting a gorgeous diamond by keeping the proportions of the diamond within the center range of the spectrum for the ideal cut proportions rating. We consider the center range to be as follows:

Total depth between 59 - 61.8%
Table diameter between 53 - 57%
Crown angle between 34.3 - 34.8 degrees
Pavilion angle between 40.6 - 40.9 degrees
Girdle thickness between thin and slightly thick
Culet: AGS pointed or GIA none

This is not to say that other combinations of crown and pavilion depth won't result in comparable light return, they certainly will which is why diamonds with a variety of proportions are listed for sale on our Private Reserve. We're just trying to simplify your quest as much as possible by providing you with a tight range that almost always works. Occasionally you will see a diamond listed in our Private Reserve with a slightly different combination of crown and pavilions and that is because we have personally evaluated the diamond and determined that the crown and pavilion angles for that particular diamond are complimentary for each other and are having a positive effect on the light return. You will rarely see a diamond listed in our Private Reserve with a pavilion angle steeper than 41.2 degrees and that is because the pavilion angle controls most of the light return for a diamond and we prefer the shallower range for pavilion angle.

If you are looking for a diamond that is absolutely "eye clean" from a top down perspective then look within the clarity range of VS2 to VVS1 with VVS1 being the high side of the range. Consider diamonds in the SI-1 clarity range if you're trying to get the biggest bang for your buck and don't mind an inclusion or two which "may be visible" without magnification. Consider diamonds graded as being VVS1 in clarity if you can't sleep at night if the shoes in your closet aren't facing the same direction. Don't accept a diamond graded by any other laboratory other than the AGS, GIA, or HRD which happens to be the diamond grading laboratory for the Belgium High Diamond Council if you're looking for the type of consistency that we are during the grading process.

You'll find a wealth of Super Ideal Cut Diamonds listed in the Private Reserve of Nice Ice. Our Private Reserve of Nice Ice contains only the finest Ideal Cut Diamonds, graded by the AGS and GIA laboratories as having the highest possible grades for polish and symmetry. Proportions are verified as being Ideal Cut using state of the art Sarin DiaMension computerized proportions analysis. We hand select all of our diamonds using very strict selection criteria to ensure you of maximum brilliance, intense fire and a level of precision that exceeds industry standards and a Gem Ex Brilliance Scope light performance analysis accompanies every diamond listed in our Private Reserve.

Remember that a more in-depth explanation of the concepts touched on here can be found in the 5 Minute Version if you are looking for more information.