Diamond Glossary
Blue–White – According
to the Federal Trade Commission, only a diamond that is either
bluish color or colorless may be referred to using this term,
therefore it is not applicable in most situations.
Bow–Tie Effect – Dark area in the center of some
fancy–shaped diamonds. Caused by the skill of the diamond
cutter. A large bow–tie in the center of a fancy shaped diamond
detracts from beauty and lowers the value.
Brilliance – The amount of white light returned to the
eye from the diamond. (In other words, how bright and sparkling
a diamond appears)
Carat – A unit measurement of weight used for precious
gemstones. 1 Carat = 0.2 Gram
(The term carat is derived from the ancient carob seed from the
locust tree, used as a medium of exchange on early pan–balances.
In the early 1900's the metric carat was established.)
Carbon Spot – Diamonds are 99.95% pure carbon; but 25
other different mineral inclusions or small crystals, have been
found within diamond as well. These are not carbon spots, but
rather small crystals that were trapped within the host diamond
as it was forming in nature. Sometimes, they just happen to be
dark in color. The most common mineral found within diamond is
diamond.
Clarity – The presence or absence of inclusions within
the diamond and blemishes on its surfaces. These slight
birthmarks of nature generally do not affect the beauty of a
stone, but they almost always affect its price. When a diamond
is examined, the size, type, position, number, color, and relief
of clarity features are observed. The diamond is always viewed
with the trained unaided eye to check for relative visibility of
clarity features.
Clarity Enhancements – A diamond's clarity can be
enhanced by several methods. Diamonds with large dark inclusions
deep inside can be laser–drilled to remove these features. Laser
drilling has been performed since the early 1970's. Or, diamonds
that have feathers reaching the surface may be fracture–filled
with chemical polymers to make these feathers less visible.
Fracture filling may be performed to improve a diamond's
clarity. The jeweler must disclose both of these enhancements.
Color – The amount or presence of body color in a
diamond. Color is an important factor to beauty, rarity, and
value because it is something a consumer can see without the aid
of equipment. The absence of color in diamonds is most rare and
highly prized. Most diamonds mined in nature have traces of
yellow, some brown or gray. When deeper colors appear, these are
called fancy color diamonds.
Color Enhancements – Fancy color diamonds can be
artificially color enhanced by radiation treatment.
For colorless (white) diamonds, man now also has the technology
to improve off–white color (K–Z) diamonds as well. These
diamonds are called Pegasus or GE–POL diamonds.
Culet – The point at the bottom of the diamond.
Cut (Make) – When the term "cut" is mentioned, most
consumers think of shape. But, cut and shape are different. Cut
refers to the proportions, symmetry, and polish of the diamond.
In its rough state, a diamond's beauty is well concealed.
Through cutting, the magnificent optical beauty of a diamond is
revealed. A diamond cutter's challenge is to balance beauty with
weight retention from the rough diamond crystal. But, because
size is important to many consumers, often cutters sacrifice
diamond beauty in order to save weight, maximizing the size of
the finished diamond.
Diamond Grading Report – An expert third party opinion of the
quality of a diamond, that contains information on
identification, enhancements, carat weight, shape outline,
measurements, and the three quality factors: color, clarity, and
cut. Many labs include diagrams, top and bottom views, of the
diamond's clarity and internal/external characteristics, called
a plot. Usually issued by an independent grading laboratory.
Dispersion – The amount of rainbow colors returned to the
eye from the diamond.
Eye–clean – A diamond in which no inclusions can be seen
with the naked eye.
Facets – The flat–faced angles that are cut into a
diamond in order to maximize it's fire and brilliance.
Fancy Color Diamond – Diamonds that display enough of a
hue, or nuance of color to be desirable, are called
fancy–colored diamonds. Color in diamonds is caused by minute
traces of other elements, such as nitrogen = yellow and boron =
blue. The rarest colors are red, pink, blue, and green.
Fancy Shaped Diamond – Any other shape besides round.
(Oval, Pear, Emerald, Princess, Radiant, Heart, etc.)
Fire – The splashes of color that you see when a light
source enters a diamond, and is refracted back out by the angle
of the facets as well as the shape, color and clarity of the
diamond.
Flourescence – A unique quality possessed by some
diamonds to give off light when exposed to specific ultraviolet
wavelengths. It is an unusual quality that can enhance the
appearance of lower color diamonds (J–Z) in certain lighting
conditions. However, when fluorescence is very strong the
diamond may have an oily appearance that detracts from beauty
and value. Only 50% of all gem–quality diamonds fluoresce, and
only 10% strongly fluoresce. When gem–quality diamonds
fluoresce, it is a bluish color.
Girdle – The circumference of a diamond at it's widest
point.
Ideal Cut – A diamond cut to optimal proportions, with
optimal polish and symmetry, and the most weight loss to produce
maximum luster, brilliance, dispersion, and scintillation.
Diamonds cut to this standard are the most valuable, with only
5% of the round brilliant diamonds on the market cut to this
standard.
Inclusion – An internal flaw in a diamond that decreases
the amount of light refraction; thereby decreasing the fire and
brilliance of a diamond, and lessening it's value.
Karat – The measure of purity of gold–24K gold is 100%
pure, 18K gold is 75% pure, 14K gold is 58.5% pure.
Luster – The quantity and quality of light reflecting
from the surfaces of a diamond.
Perfect – According to the Federal Trade Commission, only
a diamond that is flawless, colorless and well cut can be
referred to by this term. Therefore, it is not applicable in
most cases and should be avoided.
Point – There are 100 Points to a Carat. 54 points=0.54
carat
Scintillation – The sparkle, which is the combination
luster, brilliance, and dispersion when there is movement by the
wearer or light source.
Shape – Diamonds are fashioned into different shapes,
such as round brilliant, pear, oval, marquise, emerald cut,
heart, and princess cut (square).
Simulant – A material that resembles another in
appearance. The optical, physical and chemical properties are
different. The latest diamond simulant is synthetic Moissanite.
Table – The flat top surface of the diamond.
Well Cut (Excellent Cut) – Diamonds that have very good optical
beauty that fall just outside of the parameters of Ideal Cut
diamond. These diamonds are priced less than ideal cuts because
they are not as rare.
