The 4 C's

Diamond Education is understanding the 4 C’s of diamonds (colour, cut, carat, clarity) and the factors that impact diamond quality. 

Each of the C’s are graded on a scale, and can be evaluated for quality. Though some universal terminology and standard grading exists, it does vary by lab entity. The most consistent entities—and the ones we recommend gaining a certificate from—are the GIA and the HRD.


Diamond Cut specifically refers to the quality of a diamond’s angles, proportions, symmetrical facets, brilliance, fire, scintillation and finishing details. These factors directly impact a diamond’s ability to sparkle, along with its overall aesthetic appeal.

The GIA grades Diamond Cut on the scale of Ideal, Excellent, Very Good, Good, Fair and Poor. The Ideal and Excellent grades, depending on Diamond Shape, signify proportions and angles cut for maximum brilliance and fire.


Diamond Colour is graded in terms of how white or colourless a diamond is. The GIA grades diamonds from D to Z, with D being the most colourless, and Z containing noticeable brown or yellow tint.

The pricing of diamonds usually reflects these grades—sometimes significantly. In most cases, the naked eye cannot tell the difference between two adjacent colour graded diamonds, though the price difference may be significant.

The most critical aspect with Colour is to determine if it appears colourless in relation to its setting. You also want to be certain that a diamond is clear of any tinting that takes away or interferes with white and coloured light reflections. The K Colour in this Cushion Cut Diamond, for example, distracts from the sparkle of the diamond while this I Colour Diamond is radiant.


A Diamond’s Clarity grade evaluates how clean a diamond is from both inclusions and blemishes. Clarity is graded by the GIA on the following scale:


  • FL (Flawless)


  • IF (Internally Flawless)


  • VVS1 (Very, Very Slightly Included 1)


  • VVS2 (Very, Very Slightly Included 2)


  • VS1 (Very Slightly Included 1)


  • VS2 (Very Slightly Included 2)


  • SI1 (Slightly Included 1)


  • SI2 (Slightly Included 2)


  • I1 (Inclusions 1)


  •    I2 (Inclusions 2)


Depending on the size, location and darkness of blemishes and inclusions, these imperfections can interfere with light as it passes through the diamond. When this happens, the brilliance and beauty of the diamond is dulled, taking away from the high quality Cut.


For Clarity, our primary recommendation is to ensure the diamond is eye clean, and that inclusions are not interfering with light reflection.


Often when people hear the term “Carat Weight,” they think it refers to the size of the diamond. In actuality, Carat refers to the weight of the diamond, not how large the stone is. A 1 Carat Diamond equals 200 milligrams, or 0.2 grams—and weighs about the same as a quarter of a raisin. Depending on the Diamond’s Shape and how it is cut, two 1 Carat Diamonds might be quite different in size.