The cut of a diamond is the only characteristic that is within a human’s control. It is the geometric proportions to which the stone was crafted by the diamond cutter. It must be cut to precise angles, cannot be too shallow or deep, and must be polished to have a mirror finish. In order to reflect light, facets are cut to give the stone a prism-like effect.

An ideal cut is a specific cut in which the light will enter the diamond to be reflected and dispersed through the top and not the sides or the bottom. It will have good symmetry and the facets will be well aligned. It will be well polished, have a girdle that is not to thin, and a crown that is not to shallow or deep. Most importantly, the diamond will be cut to show its true brilliance.

Many diamonds will come with a diamond grading report, which is created by an independent gemological laboratory. The Gemological Institute of America does not evaluate a diamond’s cut, however the American Gem Society has it’s own rating scale which ranges from 0 (ideal) and 10 (poor). It’s a good idea to find out from your jeweler if the diamond you are interested in has been graded to determine the actual cut.


roundRound (Brilliant) The most common style of cutting for diamonds and other stones. The standard round brilliant cut diamond consists of a total of 58 facets. Modifications of the brilliant style of cutting include such fancy shapes as the marquise, oval, pear shape and many others.
princessPrincess A square shaped, modified brilliant cut diamond. The princess cut diamond is a relatively new and highly popular cut for diamond engagement rings. This cut is based on the multi-faceted square cut.
emeraldEmerald A form of “step cutting”. Usually rectangular, the emerald cut diamond has rows (steps) of elongated facets on the crown and pavilion, parallel to the girdle. It also has very pronounced corner facets.
radiantRadiant A rectangular or square shaped diamond with step-cut and scissor-cut on the crown, and a brilliant-cut on the pavilion. The radiant cut diamond has a total of 70 emerald-type facets. Some claim this is a more brilliant diamond cut than the emerald.
ovalOval A brilliant style of cutting in which the outline is elliptical or oval. The oval cut diamond is a slightly elongated version of the Brilliant, or Round, cut.
pearPear A variation of the brilliant cut, the pear cut diamond features a pear or teardrop shaped girdle outline that is rounded on one end with the other end coming to a point.
marquiseMarquise A variation of the oval cut, the marquise cut diamond features an outline of the girdle which is boat or almond shaped.
heartHeart The heart cut diamond is a type of fancy diamond cut, which is cut to resemble the popular Valentine’s Day shape.
asscherAsscher A diamond cut named for its inventor, Joseph Asscher, who in 1902 developed a square cut diamond with 74 facets. The Asscher cut diamond features wide step facets and deeply clipped corners, which make the gemstone resemble an octagon.
cushionAntique Cushion Much like the old-mine-cutm and an older form of the brilliant cut, the antique cushion cut diamond has a girdle outline approaching a square with rounded corners.
roseRose An early style of cutting diamonds, probably originated in India. The base (back) of the rose cut diamond is usually flat and the top (front) is slightly dome-shaped and covered with a varied number of triangular facets that terminate in a point, much like a shallow sided pyramid.
tycoonTycoon The tycoon cut diamond is a departure from the other branded rectangle shapes with a radical top design which is reminiscent of the early French cut. The secret of this brilliant stone is the nine crown facet design which creates a diamond-shaped table. It’s like having a diamond within a diamond.