consumer guidance. we do not sell jewelry.

2.  Shape

As the name suggests, shape is nothing more than the intrinsic shape of the diamond.  As viewed from the top, the most common shapes are:

Round Cut
Marquise Cut
Oval Cut
Pear Cut
Heart-Shaped Cut
Emerald Cut
Princess Cut
Radiant Cut

With the exception of the emerald cut, today's most popular shapes are brilliant cuts or hybrid cuts (as opposed to strict step cuts).  In terms of cost, the round brilliant tops the list, while the square cuts typically cost about 10% less for a diamond of the same weight and quality. 

Unless you're purchasing a diamond as an investment (in which case you should strongly consider a round brilliant), you should choose the shape which pleases you most.   Saul Spero, a New York diamond appraiser, spent 25 years interviewing over 50,000 people to determine if there was any correlation between personality and preference of diamond shapes.  In his book Diamonds, Love, and Compatibility, he states that if a woman has a strong preference for any of these shapes, she can be characterized as follows:

Shape Spero's Personality Traits
Round Family-centered, dependable, unaggressive.
Oval Individualistic, creative, well-organized, willing to take chances.
Heart Sentimental, feminine, sensitive, trusting.
Rectangle/Square Disciplined, conservative, efficient, honest.
Pear Conforming, considerate, adaptable.
Marquise Extroverted, aggressive, innovative, career-centered.
Unless you're buying a diamond as an investment, choose a shape that you like, regardless of its relative value or the correlation between the bride-to-be's personality and Spero's study.   Other than personal preference, the only characteristic that you should trade off if you choose one diamond shape over another is in brilliance and fire.  Continue with the tutorial to learn more.