A
diamond’s beauty, rarity and price is determined by
the interplay of all the 4C’s – carat
, colour, clarity and cut.
Only
through viewing the diamonds in person can you really gauge
your own definition of beauty and decide for yourself the
relative importance of these criteria.
But
these short explanations of the 4C’s will enable you
to understand their importance and allow you to better evaluate
diamonds and diamond jewellery.
Carat, shortened to .ct, is a measure of weight.
One carat equals 200mg. A carat is divided into 100 points
so a 50 point diamond is the same as a 0.50ct diamond or
a 1/2ct diamond.
As
larger stones are rarer they have a greater value per carat.
If quality is equal, a 1.00ct diamond will cost much more
than two 0.50ct diamonds.
Colour refers to the body colour of the diamond
rather than the surface rainbow of reflected light known
as fire. A colourless diamond, like a clear window allows
more light to pass through it, emitting more sparkle and
fire than a coloured diamond. Off-white diamonds absorb
light, inhibiting brilliance. Diamonds of a clear white
(without colour), are very rare and are valued accordingly.
Using the colour grading system established by the Gemmological
Institute of America (GIA) diamonds are graded from D (colourless)
to Z (fancy diamonds) D to G being considered white. H to
N being slightly tinted white to tinted colour.
Fancy coloured diamonds, most commonly yellow to brown but
also more rarely blue, green etc have their own criteria
for grading.
Clarity refers to the presence of imperfections
known as inclusions in a diamond. They are identifying characteristics
such as minerals, microscopic diamond crystals and fractures
which occur naturally during the formation of the diamond.
The
clarity scale devised by the GIA as an international standard,
is based on the visibility, to a trained eye, of inclusions
under 10x magnification. Ranging
from F/IF (flawless/ internally flawless), VVS1 -VVS2 (very very small), VS1–VS2 (very
small), SI1-SI2 (slightly included), I1-I3 (included, visible
to the naked eye). The higher the clarity
the greater the value of the stone. Flawless diamonds
are very rare and therefore are much more valuable. While
minor inclusions may do little to detract from the beauty
of the stone, depending on their location, nature, size
and number, some inclusions can reduce the flow of light
through the diamond, thereby reducing its brilliance. As
the nature and placement of inclusions in each diamond is
unique, particularly in larger diamonds 1.00ct plus even
similarly graded diamonds can vary greatly in beauty. Also
the importance of clarity depends on the cut of the diamond.
For example an emerald cut with its long rectangular facets
is easier to see through so inclusions are more visible
than in similarly graded brilliant cut diamonds.
Cut refers to the angles and proportions of
the diamond. In an ideal cut round brilliant diamond, its
57 or 58 facets are precisely cut to scientific formulas.
These act as a series of tiny mirrors, constantly capturing
and reflecting light and bouncing it back through the top
of the stone resulting in a display of brilliance and fire.
Each stone loses, on average more than half its original
weight during cutting and polishing. A poorly cut stone,
either cut too deep or too shallow allows light to leak
out through the sides or bottom resulting in less brilliance.
Cut is also commonly used in reference to
shape i.e. - round brilliant, square brilliant (princess),
oval, pear, heart etc. While the round cut is the most brilliant
of all diamond shapes the “fancy shapes” have
their own guidelines to be considered well cut.
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round |
oval |
marquise |
pear |
heart |
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princess |
emerald |
radiant |
cushion |
trilliant |
As
a guarantee that the quality of diamond that you are paying
for is accurate, it is recommended that the diamond be independently
graded and certified by a recognised diamond laboratory.
In
pre-set jewellery the setting affects the appearance
of the diamond. Some settings particularly rimset can
make your diamond look bigger. After setting, a diamond
cannot be as accurately graded as a loose diamond. Inclusions
located near the girdle (edge) of the diamond can be hidden
by the setting and sometimes the reflections of the setting
itself can be confused with inclusions. The colour of the
metal can be reflected in the diamond. A yellow gold setting
can make a white diamond appear lower or warmer (ie. more
yellow). J-N colour graded diamonds are complimented by
yellow gold settings as the contrast will show more in a
platinum setting. Higher quality, whiter diamonds are best
enhanced by platinum settings.
If
you are purchasing a diamond it is worth taking into account
these factors in choosing the most suitable style of mounting.
All our diamonds are from legitimate
sources not involved in funding conflict and in compliance
with UN resolutions and we hereby guarantee that the diamonds
are conflict free based on personal knowledge and/or written
guarantees.