Most are more interested in the proportions of the diamond as opposed to its shape when speaking of cut(Round Brilliant, Marquise, Pear, Princess, etc.) Every diamond regardless of its shape gets it brilliancy and scintillation (sometimes referred to as bling) by cutting and polishing the diamond facets to allow the maximum amount of light that enters through its top to be reflected and dispersed back through its top. A correctly cut, “well made”, stone allows light to enter the stone and bounce back out of the top almost like a mirror. As you can see if the angles are correct the light that enters is dispersed properly back through the diamond’s top facets.

When a stone is cut too shallow  or too deep the light that enters through the top is allowed to escape through the diamond’s bottom and does not allow the maximum beauty of the diamond to be realized.  If a diamond is cut to wide the light tries to exit the bottom.  If the diamond is cut to thin the light exits out of the sides. Click here to go back to diamond education.