4 C’s Of Diamonds

Various characteristics of diamonds are graded and categorized by the diamond industry.  Learning about diamonds is first learning about the "four Cs" of diamonds which are considered the most important grades and categories:

• Cut
• Clarity
• Color
• Carat weight

Cut

First, don't confuse diamond "cut" with "shape."  Shape refers to the general outward appearance of the diamond (such as round, emerald or pear).  When a diamond jeweler (or a diamond certificate) says "cut," that's in reference to the diamond's reflective qualities and not the shape.

Diamond cut is perhaps the most important of the four C's, so it is important to understand how this quality affects the properties and values of a diamond stone.  A good cut gives a diamond its brilliance, which is the brightness that seems to come from the very heart of a diamond.  The angles and finish of any diamond are factors that determines it's ability to handle light that leads to brilliance.

When a diamond is well-cut, light enters through the table and travels to the pavilion where it reflects from one side to the other before reflecting back out of the diamond through the table and to the observer's eye. This light is the brilliance we mentioned, and it's this flashing, fiery effect that makes diamonds so mesmerizing.

In a poorly cut diamond, the light that enters through the table reaches the facets and then 'leaks' out from the sides or bottom of the diamond rather than reflecting back to the eye. Less light reflected back to the eye means less brilliance.

Clarity

Most diamonds contain some inner flaws, or inclusions, that occur during the formation process.  The visibility, number and size of these inclusions determine what is called the clarity of a diamond.  Diamonds that are clear create more brilliance, and thus are more highly prized, and priced. 

When we speak of a diamond's clarity, we are referring to the presence of identifying characteristics on (blemishes) and within (inclusions) the stone. 

If you think about the incredible amount of pressure it takes to create a diamond and the fact that natural diamonds are not grown in a sterile laboratory, it's no surprise that most diamonds have flaws.

Basically there are two types of flaws: inclusions and blemishes. Inclusions refer to internal flaws and blemishes refer to surface flaws. However, in the diamond grades listed below, you'll note that none of the grades include the term "blemish" -- for the purposes of grading diamonds, all flaws are called "inclusions."

Inclusions include flaws such as air bubbles, cracks, and non-diamond minerals found in the diamond. Blemishes include scratches, pits, and chips. Some blemishes occur during the cutting processes (most often at the girdle). Diamonds with no or few inclusions and blemishes are more highly valued than those with less clarity because they are rarer.

How are diamonds graded for clarity?

• F - Flawless: No internal or external flaws. Extremely rare.
• IF - Internally Flawless: no internal flaws, but some surface flaws. Very rare.
• VVS1-VVS2 - Very Very Slightly Included (two grades). Minute inclusions very difficult to detect under 10x magnification by a trained gemologist.
• VS1-VS2 - Very Slightly Included (two grades). Minute inclusions seen only with difficulty under 10x magnification.
• SI1-SI2 - Slightly Included (two grades). Minute inclusions more easily detected under 10x magnification.
• I1-I2-I3 - Included (three grades). Inclusions visible under 10x magnification AS WELL AS to the human eye. We do not recommend buying diamonds in any of these grades.

Color

Colorless diamonds are the most desirable since they allow the most refraction of light (sparkle). Off white diamonds absorb light, inhibiting brilliance.

Carat Weight