Diamonds have a history of being the classic symbol of enduring love and for many will be one of the largest purchases made in their life.

Diamonds are graded and valued using a system referred to as “The Four C’s” – cut, colour, clarity and carat weight. At, we recognize the importance of being able to make an informed decision regarding your diamond purchase and below is a guide that will assist you in understanding the four C’s. Shape and certification are also important factors when considering a diamond purchase and are discussed at the end of this tutorial.



Cut may be considered the most important of the four C’s and refers to the overall description of the proportions and finish of a diamond. Cut does not refer to the shape of the diamond and many confuse the two. The proportions determine the brilliance of the diamond while the finish represents symmetry and other characteristics of the cut.

The cutter’s responsibility is to transform the rough diamond crystal into a breathtaking gem. Many precise measurements go into creating a diamond and when the cutter achieves the proper proportions and finish, light will then refract into the diamond and is reflected from one facet to another and returns through the top of the diamond, resulting in a display of white light, rainbow coloured light, scintillation (sparkling when the diamond moves) and luster.

The standard rating for cut used by the Gemology Institute of America (GIA) and the diamond industry is Excellent, Very Good, Good, Fair and Poor.

The depth and width affects how light travels within the diamond and a poorly cut diamond will have dulled brilliance.

Ideal Shallow Deep


The clarity of a diamond refers to the number, size and position of the inclusions that occur naturally and internally within the diamond. These internal inclusions are also referred to as flaws, crystals, feathers and clouds. The crystals are mineral deposits trapped inside the rough diamond and appear as black or white spots. Feathers are very small cracks that look and are shaped like a bird’s feather. The clouds are a number of small specks grouped together to create a hazy milky appearance.

However, there are some grading features that are a direct cause of the cutting and polishing process, eg: scratching on the surface, bearding, nicks and polishing lines. These small characteristics are not significant in determining value as they can, in many cases, be polished away. It is important to note that the fewer and less obvious the inclusions present in the diamond, the more valuable the diamond becomes.

The method applied to determine the clarity of a diamond is a jeweller’s loupe. This is a small magnifying glass used to view diamonds. It magnifies the object ten times, generally referred to as 10x the power of magnification. Any inclusions not detected under this power of magnification are considered to be non existent. Many laboratories will also use a power of ten microscopes with strong back lighting to accurately determine clarity.

Listed below is the grading scale used by the GIA and most other laboratories in the diamond industry.

FL, IF Flawless, Internally Flawless: No internal or external flaws. Internally Flawless. No internal flaws. These are very rare and beautiful diamonds.
VVS1, VVS2 Very, Very Slightly Included: Very difficult to see inclusions under 10x magnification. This is an excellent quality diamond.
VS1, VS2 Very Slightly Included: Inclusions are not typically visible to the naked eye and are less expensive than the VVS1 or VVS2 grades.
SI1, SI2 Slightly Included: Inclusions are visible under 10x magnification, and may be visible with the naked eye. This is a good diamond value.
I1, I2, I3 Included: Easily detectible by the naked eye. These diamonds are not recommended by


Diamonds come in a wide range of colours; however the less colour a diamond has the more rare and valuable it is. “Fancy” colour diamonds which are very rare and very expensive do not follow this rule.

Fluorescence is the light effect that some diamonds show when illuminated with an ultraviolet source. The fluorescence grades are nil, slight, medium and strong. In some instances when fluorescence is present in a diamond, it will improve the colour, but in most cases strong fluorescence is not desirable.

The colour grading system applied by the GIA and most industry standards uses the letters of the alphabet from D to Z, with D being colourless and Z having the most colour. J is considered to be the last of the white colours. Following is a diagram showing how a diamond’s colour is graded. Diamonds grades lower than J are not recommended by

Carat Weight

The weight of diamonds is expressed in carats. One carat is equal to 200 milligrams or 0.2 grams. The carat can be further broken down into points – there are 100 points to a carat. The word carat is derived from the Carob Seed which was used in ancient times to measure the weight of diamonds in pan-scales.

Diamonds are weighed most accurately when they are not mounted in a setting. The Gemological Institute of America will only grade diamonds that are not mounted. Each carat is divided into “points” described above, so a 1-carat diamond would have 100 points, ¾ carat would have 75 points and so on.

Large diamonds are discovered much less frequently then small ones which will make large diamonds much more valuable. Diamond prices will rise significantly with carat weight.

Diamond Shapes

The shape of a diamond is the geometrical form, such as round, princess, emerald, etc. Diamonds come in a wide variety of shapes and the choice should be one of personal preference. Below is an illustration of the shapes offered.

Round Brilliant Pear Marquise Oval Heart Cushion
Princess Emerald Radiant Trilliant Asschur  


Every diamond purchase from will be accompanied by a Diamond Certificate, also referred to as a grading report or dossier. The grading report is a complete evaluation of the diamond performed by qualified professionals and analyzes dimensions, clarity, cut, colour, finish, symmetry and other characteristics. There are many independent gemological laboratories that issue diamond certificates, including the following:

  • The Gemological Institute of America (GIA)
  • The International Gemological Institute (IGI)
  • European Gemological Laboratory (EGL)

Our Canadian diamond inventory is graded by GemScan International which was incorporated in 1985 as an independent jewellery appraisal laboratory providing gem identification. GemScan is located in Toronto, Ontario.

It is important to remember that none of the four C’s are mutually exclusive and that the cut, clarity, colour and carat weight must all be in balance in order to find the diamond that fits your particular budget. Please feel free to contact one of our diamond experts if you would like assistance with your diamond purchase.