Having diamonds graded professionally is not cheap, so it is a good idea to understand as much about choosing diamonds as possible. The value of an investment diamond is determined by its grade, which is in turn, determined by the ‘Rule of the four C’s’ namely Carat, Clarity, Colour and Cut.

Carat
A carat is the unit of weight by which a diamond is measured. Large diamonds are found less frequently than small diamonds and thus the price rises exponentially relative to its size. For example a 2 carat vivid yellow is more valuable than a 1 carat  vivid yellow. With coloured diamonds it is the colour and the size that determines the value of the diamond.

Clarity
Brilliance and clarity in a diamond are features of its purity; the purer the diamond the greater its clarity and brilliance. Clarity is graded by determining the size, position, brightness and number of faults in the stone (called inclusions). Diamonds with no external or internal faults are called flawless; there are very few of these in the world. Internally flawless stones have no inclusions within the diamond; other investment stones can be classified as VVS1 (very very slightly included) VVS2, VS1 and VS2 are also classified as investment quality.

Colour
Within coloured stones the colour is the most important factor relating to its value, the rarer the colour the more valuable the stone. The most common colour is yellow followed by orange, pink, green, blue and red. Please note that diamonds can be made up of more than one colour e.g. fancy intense greenish yellow.

Cut
Only master craftsmen can cut a diamond so as to release its fire, sparkle and beauty. Cutting a diamond to good proportions will result in light reflecting from one mirror like flaw in the diamond (called a facet) to another and then disperse through the top of the stone resulting in a display of brilliance and fire. It is important to note that when cutting a coloured diamond the cutter will in some cases, sacrifice weight and size to bring out a more intense colour.