Diamond Cut
A diamond's cut is considered to be the
most important of the four Cs. It is important to understand how a diamond's
proportions and the relationship between them affects its brilliance, fire, and
scintillation.
Excellent Cut Diamond
Cut, more than any other quality aspect,
gives the diamond its sparkle. A diamond gets its brilliance and scintillation
by cutting and polishing the diamond facets to allow the maximum amount of
light that enters through its top to be reflected and dispersed back. When all
the angles are correct, the light that enters is dispersed back through the
diamonds top facets.
Inferior Cut Diamonds
Most diamonds are "spread" in their cutting to retain maximum weight
from the original rough. A heavier diamond will result, but so does a dramatic
sacrifice of potential fire and brilliance. The width and depth have the
greatest effect on how light travels within the diamond, and how it exits in
the form of brilliance.
Diamond Cutters
A diamond cutter spends years mastering his craft, learning how best to cut a
rough diamond to achieve the ultimate cut with the fewest imperfections and the
least loss of carat weight. The better the cut, the more valuable the diamond.
Shallow Cut Diamonds
When a diamond is cut too shallow, light leaks out of the bottom, brilliance is
lost and the diamond appears watery, glassy and dark. A diamond with these
characteristics is referred to as a "fisheye".
Deep Cut Diamonds
When a diamond is cut too deep, light leaks out of the sides,
brilliance is lost and the center of the diamond will appear to be dark. A
diamond with these characteristics is referred to as a "nailhead".
Diamond Proportions
Experts express differing opinions on the best table
size (the diameter of the largest facet on the top of the stone) and the best
depth for a diamond, because these factors alone are not sufficient to
accurately judge its cut.
Other factors - crown angle, girdle thickness, pavilion depth-percentage (the
ratio of depth to girdle diameter), culet size, polish and symmetry - also play
a role in judging a diamond's overall cut quality.
A diamond's cut is graded by several measurements. Its depth percentage (a
measurement of the height vs. the width of the stone) and its table percentage
(a measurement of the diameter of the top facet of the stone vs. the stone's
average width) are two key factors in determining the quality of a diamond's
cut. These percentages are detailed on the GIA Gem Trade Laboratory Diamond
Grading Report that accompanies every Adiamor loose diamond.
Polish & Symmetry
Although polish and symmetry are graded under 10X magnification they can both
have an effect on the overall appearance of a diamond. Polish refers to the
quality of the diamond's surface and includes such features as nicks, polish
lines and abrasions. Symmetry refers to the exactitude of the shape and
alignment of the facets.
Off-center culet
Facets not properly pointed
Misshapen facets
Crown and pavilion misalignment
Off-center table
Table and girdle not parallel
