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.
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
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.
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.