Diamond Cut

It is certainly true that high grades of clarity, color, and carat weight greatly contribute to a diamond's appeal. But experts agree that it is the cut of a diamond that ultimately gives the stone its defining characteristics. The symmetry of a diamond's facets is determined by its cut as well as the stone's overall proportions and its ability to reflect light. A diamond that is expertly cut will possess high levels of sparkle, brilliance, and durability. A poorly cut diamond generally results in a dull, muted effect. This is true even if the diamond is graded well in all other areas.

The Anatomy of a Diamond

A diamond is basically made up of five main components. These are:

• The Table. The flat surface on the top of the stone is called the table. It is the largest facet of a diamond.
• The Crown. The top portion of a diamond is called the crown. It is located just above the girdle and extends downward below the table.
• The Girdle. The girdle forms the outer edge of a diamond where the crown and pavilion meet.
• The Pavilion. The pavilion is located at the bottom of a diamond between the girdle and the culet.
• The Culet. The smallest facet of a diamond is called the culet. It is located at the very bottom tip of the stone.

The Effect of Light on a Diamond

A diamond can be considered somewhat of a miracle of nature. No two are ever alike. Time, place, and chance play large roles in the formation of a diamond and it is this very uniqueness which gives diamonds their timelessness and desirability.

Diamonds are famous for their ability to transmit light. This quality is what gives diamonds their "sparkle". Many people confuse a diamond's cut with its shape but it is really a diamond's cut grade which determines how well a stone's facets will interact with the light. A diamond's shape, whether round, or pear, or emerald, will not make up for a poorly cut stone.

The cut of a diamond has three basic attributes:

• Brilliance. This is the amount of light which a diamond reflects.
• Scintillation. This is the light pattern given off when a diamond is moved.
• Fire. This is the release of light as it flows into the various colors of the spectrum.

When determining the value of a diamond, the cut generally refers to three specific factors: proportions, polish, and symmetry. The Gemological Institute of America (GIA) introduced its diamond cut grading system in early 2005 after years of exhaustive research and testing. This scale assigns a grade to each diamond tested that ranges from Excellent to Poor.

Cut and Depth of a Diamond

There are generally three main types of cuts associated with diamonds. How expertly a stone is cut will largely determine the brilliance and fire of a particular diamond.

• Shallow Cut. A shallow cut can make a diamond seem larger than it actually is. But this lack of depth allows light to escape from the sides of the stone rather than capturing it at the top of the diamond and reflecting it properly.
• Ideal Cut. As the name implies, an ideal cut diamond reflects light beautifully and is well-proportioned. A diamond possessing this cut generally has a much-desired, luminous appearance.
• Deep Cut. A diamond with a deep cut reflects light poorly. This results in a stone that has a muted, dull appearance.