Fancy-shaped diamonds are defined as any non-round diamond. Fancy shaped diamonds are ususally less expensive than round diamonds.

The most common diamond shape is round. It has more brilliance and dispersion. Fancy cut stones have less due to their shape.

For more information on round diamonds, see round diamonds.

There is one quality which can affect the cost of a diamond and that is shape appeal. The best way to judge shape appeal is to look at the diamond's outline without a loupe (10x magnifier) and decide if it's attractive to you.