Color, Clarity, Cut & Carat Weight
Anatomy of a Diamond
GIA 4Cs
COLOR
The GIA Color Scale extends from D
(colorless) to Z (light yellow or brown).
Although many people think of gem quality
diamonds as colorless, truly colorless diamonds
are actually very rare. Most diamonds used in
jewelry are nearly colorless with tints of yellow
or brown.
Color grades are determined by comparing
each diamond to a master set. Each letter grade
represents a range of color and is a measure of
how noticeable a color is.
Fluorescence Some diamonds can emit a visible
light when exposed to ultraviolet radiation, but
fluorescence is not a factor in determining color
or clarity grades. However, a description of its
strength and color is provided on GIA Reports
as an additional identifying characteristic.
CLARITY
The GIA Clarity Scale includes eleven
clarity grades ranging from Flawless to I3.
Because diamonds form under tremendous
heat and pressure, it is extremely rare to find
a diamond that lacks any internal and external
characteristics. These characteristics are a byproduct
of its formation and help gemologists
separate natural diamonds from synthetics and
simulants, and identify individual stones.
CUT
The GIA Cut Scale ranges from Excel lent
to Poor. GIA provides a cut quality grade for
standard round brilliant diamonds that fall in the GIA
D-to-Z color range.
A polished diamond’s beauty lies in its complex
relationship with light: how light strikes the surface,
how much enters the diamond, and how, and in what
form light returns to your eye.
The result is a magnificent display of three attributes.
Brightness is the combination of all white light
reflecting from the surface and interior of a diamond.
Fire describes the “flares” of color emitted from
a diamond. Scintillation describes the flashes of
light you see when the diamond, the light, or the
observer moves.
A polished diamond’s proportions affect its light performance,
which in turn affects its beauty and overall appeal. Diamonds with
fine proportions, symmetry, and polish optimize their interaction
with light, and have increased brightness, fire, and scintillation.
CARAT WEITHT
One carat equals 200 milligrams in weight.
For diamonds under one carat, each carat is divided into
100 points – similar to pennies in a dollar. 0.75 ct. = 75
points, 1/2 ct. = 50 points.
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