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The shape of a diamond describes its appearance when viewed from above. Through different cutting processes a diamond takes a variety of shapes. While all diamond shapes have special attributes, the overall choice will depend on your personal preference.

Popular Stone Shapes:

Asscher Cut
This shape has a pavilion that is cut with rectangular facets in the same style as the emerald-cut. However, it has cropped corners giving it a square appearance. This square emerald diamond is made with the step-cut process. It is bright, shiny and clear. This stone shape is best when set with a prong setting such as a four prong or six prong style.

Brilliant Cut / Round
The most popular diamond shape is currently the round-brilliant cut. This diamond cut is optically brilliant diamond because of its 360-degree symmetrical shape. For a large amount of sparkle and a classic shape, the round-brilliant is a great choice. This stone shape also works well with nearly all mounting types including four prong, six prong, channel, bezel, half-bezel and illusion.

Also known as “pillow cut” diamonds, the cushion is an antique cut that has both a classic and romantic appeal. The Cushion-Cut diamond has 58 larger facets and rounded corners which increase its brilliance. There are square and rectangular variations of cushion cuts.

The classic cut emerald has a unique pavilion that is cut with rectangular facets to create a distinctive optical appearance. Due to its larger, open table, this diamond shape showcases the clarity of a diamond the best. The blocked corners are usually cut to a rectangular outline, but can be cut in a square shape. Since they can vary greatly in how rectangular they are and your preference is for an emerald cut with a squared outline, look instead at the Asscher-cut diamond.

Half Moon
There are two varieties - step cut half-moons and (the more common) brilliant cut half moons. Half moons can be proportioned differently - chubby ones being less elegant and desirable than the slim elongated type.

The ultimate expression of romance and love, the heart shaped diamond is cut with triangular and kite-shaped facets which reflect light. Generally there are 59 facets on a heart shaped diamond. The cut is similar to a pear shaped diamond, except the cleft at the top of the heart shaped diamond is strategically cut to remove inclusions without affecting the total diamond weight.

The marquise cut is another brilliant-cut diamonds whose elongated shape can maximize the carat weight, giving you a larger carat weight per stone. Featuring narrowing points at both ends of the diamonds, this shape tends to flatter the finger well because it makes it appear longer. This shape works great in a solitaire setting or when paired with beautiful side stones.

The oval cut has beautiful brilliance very similar to a round-brilliant cut. An oval shape combines the sparkle of the round shapes with a finger flattering, elongated outline. It makes a good choice for someone who wants something more unique but still wants the fire and brilliance of a round cut diamond. The relatively symmetrical shape lends itself well to a variety of mounting styles. Most oval cuts work in a mounting with six prongs properly spaced for security.

The less common but visually interesting pear shaped diamond is a unique variation of the round diamond cut. there are generally 58 facets which allow the light to pass through it just as well as the round diamond cut. It is a popular choice for many solitaire diamond engagement rings or diamond rings with side stones.

The princess cut is the 2nd most popular diamond shape because of its modern classic shape offering clean lines and immense sparkle. A princess cut has either a square rectangular appearance depending on the way it was cut. The cutting process utilizes the step-cutting of the emerald cut with the triangular facets of the brilliant cut. Princess cuts will work best in a prong or channel setting.

The distinctive trimmed corners give a radiant cut its beautiful appeal. This diamond shape combines a square or rectangular shape with the brilliance of the traditional round cut. It combines the Round Cut style and the Emerald Cut style to make a non-traditional diamond. A radiant cut looks great in a solitaire setting or when prong set with side stones.

Shields are beautiful whether they are step or brilliant cut. They are great transitional stones that could be paired with virtually any center stone. The most elegant ratio is 1:1 but even elongated they are elegant, complimentary, and appropriate companions to the center stone.

Square Cushion
This diamond shape combines a square cut with rounded corners, much like a pillow (hence the name). This classic cut has been around for almost 200 years, and for the first century of its existence was the most popular diamond shape (similar to round cut today).

Square Radiant
The radiant cut diamond is the first square cut to have a complete brilliant-cut facet pattern applied to both the crown and pavilion, creating a vibrant and lively square diamond. The cropped corner square shape of the radiant is a nice bridge between a cushion and a princess cut, and for that reason looks beautiful set with both rounded and square cornered diamonds.

Straight Baguette
Elongated rectangular step cuts could be set either north-south or east-west. When set north-south they are commonly staggered on top of each other forming a ladder-like element. This is the only way they could appear in a modern ring. Set any other way they would contribute to creating an Art Deco look.

Tapered Baguette
These are the most common side stones used in engagement rings. Some might argue that a ring with tapered baguettes should not be called a three stone ring; it should be called a solitaire.  This is because baguettes are really not an extension of the center stone. They are set on the "cathedral' part of the shank.

Trapezoid diamonds are tapered on both ends to form a trapeze. This perspective view of straight baguettes allows for a graceful transition from a large center stone to a narrow shank of the ring. They work great with other step cut stones such as an emerald cut or Asscher cut. They are also a nice fit as part of a traps/bullet combination, which is popular in five stone rings.

Triangular Brilliants, also known as Trillions and Trilliants, are mixed cuts with three equally straight or slightly curved sides. They are typically shallow and often seen as side stones for other fancy shapes, but when well proportioned, one can also be a stunning centerpiece in an engagement ring.