Of course, the most popular and commonly seen shape for diamonds is the round or brilliant cut, which has 57 or 58 facets (depending on whether the culet, or point at the bottom of the stone, is faceted or not). It's the 'classic' shape that most people think of when they think of a diamond. But the round cut is by far not your only choice. All shapes are capable of fantastic fire and brilliance. The only difference is the result of the diamond cutter's decision to cut the rough diamond into that particular shape.

Round Brilliant
The most classic cut

Marquise
An elongated brilliant-cut stone with a point on each end

Princess
Typically a four-sided square to slightly rectangular brilliant cut

Radiant
Typically a slightly rectangular to square diamond

Emerald
A traditional octagonal cut usually rectangular

Asscher
Often referred to as a "square emerald cut", this stone is step-cut and square with cropped corners

Heart
More fanciful cut, shaped just as it sounds

Oval
Reminiscent of the round brilliant cut, both in sparkle and shape

Pear
Combines the brilliance and form of a round stone with the elongated elegance of a marquise

Choosing the best shape for you

The most important factor in determining shape, of course, is what appeals to you, and what looks best on your hand. Longer and shorter stones can visually affect the appearance of your hands, making them look longer or shorter in return. Also, your taste may guide you toward more traditional shapes, like the classic round brilliant, or toward less conventional shapes like pear, marquise or heart. While the shape of the diamond you choose is ultimately a matter of personal preference, there are differences in the various shapes that affect their brilliance, apparent size and value:

• Round brilliant-cut diamonds show the most brilliance and sparkle of all the shapes. When it comes to hiding imperfections, the round brilliant cut is the king. Its design allows it to hide flaws and yellow tints better than diamonds of other shapes. In emerald cuts and baguettes, which have long, flat facets, flaws become the most obvious.
• Emerald cuts, while sleek and attractive, are not quite as brilliant. If you like the square or rectangular shapes of an emerald cut, you may want to consider a radiant, princess or quadrillion, which have more facets and therefore more brilliance.
• If you want a diamond that looks as big as possible, even if it doesn't weigh much, consider a fancy shape like a marquise or pear, which appear bigger and longer than round diamonds of the same carat weight.