The 4 C's of Diamonds

4 C’s of Diamonds - Explained.

While shopping for diamond engagement rings, you will undoubtedly come across the concept of the 4 C’s. Together, the 4 C’s — Cut, Colour, Clarity and Carat Weight contribute to the overall beauty of a diamond. Which of the 4 C’s are the most important? Let us explain!

Arguably the most important aspect to consider when buying a diamond, the diamond’s cut refers to the quality of angles, proportions, symmetry, brilliance, fire, scintillation and finishing details. These factors are what makes a diamond sparkle and have a major impact on its overall aesthetic appearance. The Gemological Institute of America (GIA) grades Diamond Cut on the scale of Ideal, Excellent, Very Good, Good, Fair and Poor.

Diamond Colour is graded in terms of how colourless the diamond is. The GIA grades diamonds from D - Z, with D being the most colourless and Z containing an obvious yellow or brown tint. The way diamonds are priced can be significantly impacted by their colour. 

A diamond’s clarity takes into account how clean a diamond is from 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)

When it comes to a diamond’s clarity, it’s best to take into consideration how “eye-clean” a diamond is. “Eye-clean” refers to diamonds that may have inclusions if you look at them with a magnifying glass, but are unseen to the naked eye.

Carat Weight

Contrary to popular belief, a diamond’s carat weight refers to the weight of the diamond, not how large the stone is. For example, 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 could actually be quite different in size.

Diamond shapes

Round Brilliant


Heart Shape




Pear Shape



Clarity - Grading Scale


Internally Flawless - The inner workings of the diamond is free from visible blemishes under 10x magnification. Small external details are tolerated.

VVS-1 | VVS-2

Very Very Slightly Include - Inclusions and/or external blemishes are very difficult to see under 10x magnification.

VS-1 | VS-2 

Very Slightly Include - Inclusions and/or external blemishes are difficult to locate under 10x magnification. 

SI-1 | SI-2

Imperfect - Inclusions and external blemishes are easy to locate under 10x magnification.

I-1 | I-2 | I-3

Imperfect - Heavy inclusions are easy to locate with the naked eye.

Colour - G.I.A Colour Grading

DEF - Colourless

GHJ - Near Colourless

KLM - Slightly Tinted

NOPQR - Very Light Yellow

STUWXYZ - Light Yellow to Yellow