It is the cutters skill that releases the beauty of the diamond. Depending upon the stone and the cutting shop, the diamond could have a poor cut (to retain as much weight, and not it's true beauty). Or the stone could have an ideal cut (where the most beautiful and bright stone is cut from the rough diamond).

In a properly proportioned diamonds the light is reflected from one facet to another and then dispersed through the top of the stone to give you a diamond that looks like a ball of fire.

In a diamond that is cut too deeply, some light escapes through the sides and the stone looses some brilliance because of the light leakage.

The same light leakage is the reason shallow cut diamonds lack luster. Some of these stones look like a Fish Eye, because the center is dark with no life.

Do not confuse the cut on a diamond with the shape of a diamond. Shape would be square or princess cut, round cut, marquise, etc. Your personal preference for the shape is up to you. I like round cut, which is still the most popular, followed by the princess cut.

Find a custom jeweler in Springfield, or internet jeweler.