CUT

The most important of the 4 Cs is the cut of the diamond because cut has the greatest effect on a diamond’s beauty.  The cut of a diamond is different from the shape; diamonds are cut into many shapes (round, square, rectangular, etc.) depending on the nature of the rough stone.  A well-cut diamond is the work of a master diamond cutter who has the knowledge and experience to maximize the performance of the diamond.  When a diamond has been cut to ideal proportions, the diamond will better reflect light thus making the diamond “sparkle”.

The factors that contribute to the proportions of a diamond are the diameter, table, crown, girdle, pavilion, culet and depth.  These factors are defined under the proportions link.  Also contributing to the performance of the diamond cut are polish and symmetry.  Polish refers to the smoothness of the diamond facets and symmetry refers to the alignment of the facets.  These are further defined under the proportions link.

COLOR

Diamonds are graded from D (colorless) to Z (light yellow or brown).  D color diamonds are extremely rare and necessarily much more expensive.  G-H and I-J graded diamonds are near-colorless, but not nearly as rare as colorless and are therefore an excellent value.

CLARITY

Clarity is a measure of the internal features (inclusions) and surface characteristics (blemishes) of the diamond.  Diamond clarity is graded from Flawless to Included with the eleven clarity grades being:

• FL, IF              Flawless, Internally Flawless
• VVS1, VVS2   Very, Very Slightly Included
• VS1, VS2        Very Slightly Included
• SI1, SI2           Slightly Included
• I1, I2, I3          Included

VS and SI graded diamonds, depending on the shape and cut, will be eye-clean and the inclusions will not detract from the beauty of the diamond.

CARAT

The carat is the standard weight measurement for faceted stones.  Carat is not a measurement for size of the stone and varies with the density of the gem.  A one carat round diamond  and a one carat round ruby will not be the same diameter.

Proportions

Diameter:  The width of the diamond measured at the girdle.

Table:  The largest facet of the diamond.

Crown:  The top portion of a diamond extending from the girdle to the table.

Girdle: The intersection of the crown and pavilion.

Pavilion:  The bottom conical portion of the diamond, extending to the culet.

Culet:  The facet at the bottom of the diamond.

Diamond Certificates

Diamond certificates or grading reports come with diamonds that are certified and have been graded by a gemologist.  Not all diamonds are graded or come with a certificate.  The diamond certificate lists the specific characteristics of the diamond such as color, clarity, carat weight, shape, symmetry, proportion and description of the diamond cut along with a diagram of any notable internal or external specifics of the diamond.