COLOUR
To the naked eye, diamonds often appear colourless or white, but in fact this is rare. Most diamonds have a faint yellow or brown tint caused by other elements that combined with them when they were being formed. Colour is graded from D (colourless) through to Z (yellow). Truly colourless diamonds are extremely rare and among the most valuable. As the colour deepens Ð even though minutely Ð the value of diamonds changes significantly. Beyond Z is a range of fancy colours where the diamond's colour is deep and rich. For example yellow, pink and blues. These vivid stones are also exceptionally rare.

CLARITY
a totally flawless diamond is very rare indeed and extremely valuable. Often invisible to the naked eye, the size, quantity, colour and position of inclusions are studied with a 10X jeweller's loupe to determine a diamond's clarity. Less than 1% of gem quality diamonds ever found have no inclusions and can be called flawless or internally flawless, graded FL or IF. The fewer and smaller inclusions, the rarer and more valuable the diamond. Very pronounced inclusions, which can be seen without the aid of a magnifying glass, are graded Pique 1 to Pique 3.

CUT
While colour, clarity and carat weight are all governed by nature, it takes unique skills of the diamond cutter to release the truth, breathtaking beauty of the stone. Diamonds are so hard that only diamond can cut or scratch diamond. Yet, for all its hardness, the cutting and polishing of a diamond is a delicate art.

CARAT
The weight of diamonds, as with all gems, is measured in carats. This is a unit of weight that was originally based on the seeds of the Carob tree, which early in the last century, was fixed at 200milligrams.