Know Your Jewellery

The 4 C's

Diamond Anatomy & Cut Quality

Understanding the 4 C’s of Diamonds Shopping


Clarity is the relative absence of inclusions and blemishes. Clarity grades are based on the number, size, relief, position and nature of the inclusions that can be seen under 10x maginification by a trained grader.


The cut of a diamond can affect a diamond’s appearance. Precise workmanship is required to cut a diamond so its proportions, symmetry, and polish maximize brightness, scintillation, and fire.

Diamond Cut Descriptions

The Cut is a measure of proportions of the diamond.

The Cut determines

  • The diamond’s brilliance and beauty
  • The diamond’s ability to reflect light
  • The diamond’s proportions, symmetry, and finish

A well-cut diamond appears brilliant and fiery, while a badly cut diamond looks dull and lifeless, despite having a good color and clarity grade.

The Cut is a set of measurements based on how light travels within the diamond and exits from the top. The Cut is the only “man-made” C of the 4C’s.

Gemmologists consider Cut the single most important factor that defines the brilliance of a diamond.

Do not confuse Cut with Shape. Cut refers to how well the diamond has been designed and proportioned by the cutter. Shape refers to the general silhouette or outline of the diamond.

An ideally proportioned diamond is cut according to scientific formulae calculated to maximize brilliance. In such diamonds, the light that enters the stone from the top will bounce about within the diamond to create multiple reflections, which exit the stone from the top, causing the diamond’s glitter.

Diamonds that are cut too deep or too shallow lose or leak light through the side or bottom. The result is less brilliance and ultimately less value for the diamond.

The most important proportion is the ratio between the depth and the diameter of the diamond. The ideal ratio is 58.5%, but slight deviations are acceptable. The ratio between the height of the crown and that of the pavilion is also important. Please remember that this ideal ratio applies only to the Round Brilliant shaped diamonds. Gemologists differ on the ideal depth percentages to be followed in the other fancy shapes, and therefore, no ratios have been set as ideal for any of the other shapes.

Other factors that count are the length of the pavilion facets, size and shape of the various crown facets, size of the table and the culet.

Polish and Symmetry


  • Dramatically amplifies the brilliance of a well-proportioned diamond
  • Is crucial in diamonds of very high clarity grades


  • Gives the diamond its final appearance
  • Is crucial to its brilliance
  • Ensures smooth passage of light through the diamond

Diamonds with poor polish are less brilliant due to microscopic polish lines that reduce the amount of light that enters and exits the stone.

Rating of the Cut

The Gemological Institute of America (GIA), the authority in diamond certification, grades diamond cuts as Excellent, Very Good, Good, Fair, or Poor.

The GIA determines cut grades on the basis of:

  • Brightness, Fire, and Scintillation
  • Weight Ratio and Durability
  • Polish and Symmetry

What is the best cut grade

  • All our diamonds are full-cut (also, known as double-cut) and are fully white, so any diamond purchased from us will give you the optimum balance of price, value, and satisfaction.
  • There is no BEST, this so because, “Best” is something that is subjective, as the purpose of jewellery or owning diamonds can vary from gifting to personal use to investment to weddings to emotions. What is best is what YOU like and are happy with.


GIA’s D to Z scale measures the colorlessness of a diamond, comparing it to masterstones under controlled viewing conditions.

Carat (Size)

Diamonds are sold by weight. One carat is equal to 0.20 grams. Only one in 1000 diamond weighs more than a carat.

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