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Diamonds - The 4C's
Men first discovered diamonds 4,000 years ago in the
riverbeds of the Golconda region of India. The Romans thought diamonds were splinters of fallen
stars. Each diamond is unique and is graded by 4C¢s: carat
weight, cut, clarity, and color.
They determine how much a diamond is worth. Two diamonds of equal weight may have vastly
different values, depending on their cut, clarity and color. 1.
Carat Weight The carat is the standard unit of weight for diamonds and
most other gemstones.
The term "carat" was derived from ancient times when
diamonds were weighed against the carob bean which weighed one-carat. A
one-carat polished diamond requires the mining of 250 tons of ore. The
metric carat equals 0.2 gram. One
carat is divided into 100 points, so a 50 points diamond is 1/2 carat or 0.5
carat. To choose the best carat
weight of diamond, consider your style, the size of your finger, the size of
your setting, and your budget. 2.
Cut The
proportions and finish of a polished diamond are its cut, or make. Cut can also mean shape, as in round
brilliant cut or princess cut.
Proportions are the size and angle relationships between the facets
and different parts of the stone.
Finish includes polish and details of facet shape and placement. Cut
affects both the weight yield from rough and the optical efficiency of the
polished stone. The
diamond will be more valuable if the cutter can balance these considerations
because the cut of a diamond determines
its brilliance. When the
diamond is cut to good proportions, with scientific established parameters
followed correctly, light will be perfectly refracted through the facets
returning to the eye. When light
passing through is properly refracted, it can give maximum brilliance or sparkle
(fire) to the diamond. Diamond
measurements are calculated and applied to a cut grading scale that makes it
easy to understand how well each reflect light. The cut grade system includes ratings of Excellent, Very
Good, Good, Fair and Poor.
3.
Color Grading color in the normal
range involves deciding how closely a stone's body color approaches
colorlessness. It is commonly believed that most diamonds are colorless. However, most diamonds are mined
in a range of color, white to faint yellow or brown, to the very rare fancies
such as pink, blue and green. Grading
color is to decide how closely a stone's body color approaches
colorlessness. A diamond can divide light into a spectrum of colors and
reflect this light as colorful flashes called fire. Just as when looking through colored glass, color in a
diamond will act as a filter, and will diminish the spectrum of color
emitted. The less color in a
diamond, the more colorful the fire, and the better the color grade. The color grading scale starts
at D (colorless) and proceeds down the alphabet. D ¾ F : colorless, the most valuable G ¾ J : near colorless K ¾ M : faint
yellow or faint brown N ¾ R : very
light yellow or very light brown S ¾ Z : light yellow or light brown 4.
Clarity Clarity refers to a stone's
relative position on a flawless-to-imperfect scale. Diamonds have internal features, called inclusions, and
surface irregularities, called blemishes. Together, they're called clarity
characteristics. The size,
number, position, nature, and color or relief of characteristics determine
the clarity grade. Fewer and smaller inclusions and
blemishes result in increased passage of light. This is the essence of a
diamond's brilliance and fire.
If a diamond shows no inclusions or blemishes when examined by a
skilled gemologist under 10-power magnification and other factors are
equal, it is the most valuable. The Clarity Scale for diamonds
is as follows. FL (Flawless) : no blemishes or inclusions
VVS1
and VVS2 (Very Very Slightly Included) : contain minute inclusions that are
difficult to locate. VS1
and VS2 (Very Slightly Included): contain minor inclusions ranging from
difficult (VS1) to somewhat easy (VS2) SI1
and SI2 (Slightly Included): contain noticeable inclusions which are easy
(SI1) or very easy (SI2) to see. I1,
I2, I3 (Included): contain inclusions which are obvious. It can often be easily seen face-up
with the unaided eye. The
potential durability, transparency and brilliance of the diamond will be
seriously affected. Contact Us For any further queries, please feel free to
contact us by email, cs@supreme-gems.com. |