When a round diamond has been cut to "Ideal" proportions by a master cutter, it is a splendor to behold. The Ideal Cut Diamond describes a round brilliant diamond that has been cut to exact and mathematically proven proportions. Its symmetry, with 58 exactly placed facets, produces the ultimate in luster and beauty. When a diamond is cut to the ideal proportions, all of the light entering from any direction is totally reflected through the top and is dispersed into a display of sparkling flashes and rainbow colors.

Light* entering the diamond reflects internally from facet to facet and is reflected back through the top only, creating maximum brilliance.

When a diamond is cut too deep, light* leaks out of the bottom, brilliance is lost and the center of the diamond will appear to dark. 

When a diamond is cut too shallow, light* leaks out of the bottom, brilliance is lost and the diamond appears watery, glassy and dark.