Because diamonds are formed deep within the earth, under extreme heat and pressure, they often contain unique birthmarks, either internal (inclusions) or external (blemishes). Diamond clarity refers to the absence of these inclusions and blemishes. Diamonds without these birthmarks are rare, and rarity affects a diamond’s value. Using the GIA International Diamond Grading System™, diamonds are assigned a clarity grade that ranges from flawless (FL) to diamonds with obvious inclusions (I3). Every diamond is unique. None is absolutely perfect under 10 x magnifications, though few come close. Known as Flawless diamonds, these are exceptionally rare.

The GIA Clarity Scale contains 11 grades, with most diamonds falling into the VS (very slightly included) or SI (slightly included) categories. In determining a clarity grade, the GIA system considers the size, nature, position, color or relief, and quantity of clarity characteristics visible using 10x magnification.

Cut is the factor that fuels a diamond’s fire, sparkle and brilliance.

The traditional 57 facets are in a round brilliant diamond; each precisely cut and defined is as small as two millimeters in diameter or more. The allure of a particular diamond depends on 4C and cut is one of that.

Though extremely difficult to analyze or quantify, the cut of any diamond has three attributes: brilliance (the total light reflected from a diamond), fire (the dispersion of light into the colors of the spectrum), and scintillation (the pattern of light and dark areas and the flashes of light, or sparkle, when a diamond, or the light source or the observer moves).

Round is the shape used in most diamond jewelry. All other shapes are known as fancy shapes. Traditional fancy shapes include the marquise, pear, oval and rectangle. Hearts, triangles and a Variety of others is also gaining popularity in diamond jewelry.

Diamonds and other gemstones are weighed in metric carats: one carat is equal to 0.2 grams. Just as a dollar is divided into 100 pennies, a carat is divided into 100 points. For example, a 50-point diamond weighs 0.50 carats. But two diamonds of equal weight can have very different values depending on the other members of the Four C’s: clarity, color and cut. The majority of diamonds used in fine jewelry weigh one carat or less.

Because even a fraction of a carat can make a considerable difference in cost, precision is crucial and rounded to a hundredth of a carat. Diamond weights greater than one carat are expressed in carats and decimals for instance, a 1.08 ct. stone.