Diamond Characteristics

The value of a diamond is determined by its grading. Recognized Diamond Laboratories (EGL, GIA, DIA, JCSA) grade diamonds according to the 4 Cs.

The 4Cs

• CUT
• COLOUR
• CLARITY
• CARAT

Cut

This is the shape of the diamond, and can be established with the naked eye. A round brilliant cut diamond has 58 facets, which must be in perfect proportion, ensuring light is reflected to the top of the diamond. This gives the diamond its beautiful ‘life'.

The original shape of the rough diamond often determines the shape of the cut and polished diamond, e.g. pear shape. The number of facets of fancy shaped diamonds may vary.

During the cutting and polishing process a minimum weight loss of 50% occurs, and the challenge of any diamond cutter is to minimize this weight loss.

Colour

The perfect white diamond has no colour, and is graded as D. Going down the alphabet, between D to J, diamonds are graded as white. From K to Z, a yellowish tint may be detected. Jewellery diamonds technically often have a hint of colour, which makes it more affordable, although it looks white to the naked eye. Natural fancy coloured diamond prices are determined by the intensity of the colour, clarity and rarity.

Recommended colours for jewellery diamonds are:

Yellow / Red gold: H, I, J, K, or better.

White gold and platinum: G, H, I, or better.

Clarity

Clarity refers to the purity of the diamond. Most diamonds have minute inclusions, both in or outside. These non-crystallized carbon specs can be white or black. Ideally one should choose a jewellery grade diamond with inclusions that cannot be detected by the naked eye.

Recommended clarity for round jewellery diamonds: VS1 to SI2, or better.

Emerald cut jewellery diamonds: VS1 to VS2, or better.

Carat

This refers to the weight of the diamond.

1 Carat = 100 points = 0.2 grams = approximately 6.5 mm round diamond.