The
AGSL uses a slightly different color grading scale. The AGSL
ranks the stones from 0-10, in 0.5 increments with 0 representing
the equivalent of colorless D stones, and 10 representing
the equivalent of X, Y and Z colored diamonds.
We
Can Mask Subtle Color Differences:
Our
diamonds offer a little flexibility in color selection. Because
our diamonds are designed to maximize brilliance and scintillation
they also tend to mask subtle color differences making H and
I color diamonds appear beautifully white. H and I color diamonds
tend to appear whiter than poorly cut diamonds of the same
color. Color can save you money.
A
diamond's color grade does not pertain to the "face-up" look
of a particular diamond, but rather to the "body" color of
the material. The best way to assess diamond color is to view
it from the side, un-mounted, against a white background,
using a daylight fluorescent bulb.
An
AGS Triple Ideal Cut Hearts & Arrows diamond reflects
more than 99% of the light back through the crown. There is
virtually no light leakage in these stones. What this means
to you is that rather than seeing the diamond's color, when
you look at a Hearts & Arrows diamond, all you see is
white light and scintillation. These diamonds appear whiter
than non-Ideal diamonds. Keep this in mind if budget is an
issue. By dropping one color grade in an AGS Triple Ideal
Cut Hearts & Arrows diamond, you will not be giving up
anything in the look of your diamond and you will be saving
money.
CLARITY
The
diamond's clarity is a description of its internal purity.
With fewer imperfections within the stone, the diamond is
more rare and has a higher value. The clarity scale was developed
by the Gemological Institute of America (GIA) to quantify
these imperfections. The American Gem Society (AGS) uses the
same standards as the GIA; however, the AGS uses a numerical
system where "0" is the cleanest (GIA "IF") and "10" is the
most imperfect (GIA "I3").
All
diamonds are systematically graded and plotted under 10X magnification.
If a trained grader cannot see a clarity characteristic at
10X, it does not affect the clarity grade.
Five
Factors That Determine Clarity
* Size
* Number
* Position
* Nature
* Color
All
of the above factors are taken into consideration when a diamond
is assigned a clarity grade.
Clarity
Grades Defined by the GIA
Flawless
— Flawless diamonds have no inclusions or blemishes when viewed
under 10X magnification by a skilled grader. A diamond can
have naturals confined to the width of the girdle, extra facets
on the pavilion that are not visible face-up, laser inscriptions
confined to the girdle and internal graining that is not white,
colored or reflective.
Internally
Flawless (IF) — An IF diamond has no inclusions, only blemishes
when viewed under 10X magnification.
Very
Very Slightly Included (VVS1 and VVS2) — VVS diamonds contain
minute inclusions that are difficult for a skilled grader
to see under 10X magnification. The inclusion in a VVS1 diamond
are extremely difficult to see face-up, or may be visible
only through the pavilion. Inclusions in a VVS2 diamond are
very difficult to see. Typically VVS diamonds have a pinpoint
or two; however, characteristics like a bearded girdle or
tiny chips might also be present in VVS diamonds depending
on their visibility.
Very
Slightly Included (VS1 and VS2) — Diamonds of VS clarity contain
minor inclusions that range from difficult (VS1) to somewhat
easy (VS2) to see under 10X magnification. Typical inclusions
in VS diamonds include small crystals, feathers and distinct
groups of pinpoints.
Slightly
Included (SI1 and SI2) — Diamonds of SI clarity contain noticeable
inclusions that are easy (SI1) or very easy (SI2) to see under
10X magnification. Typical inclusions, such as crystals, clusters
of pinpoints and feathers, are centrally located.
Included
(I1, I2, and I3) — Diamonds in the 'I' clarity range contain
inclusions that are obvious under 10X magnification. These
inclusions can often times be seen face-up without magnification,
sometimes affect the stone's durability and can be so numerous
or large that they affect transparency and brilliance.
The
clarity is typically assigned by a first impression or at
first glance. The grader notes whether the inclusions are
easy, difficult or very difficult to see when they first look
at the stone. The clarity grade of most diamonds is determined
in less than 2 minutes. The exception to this is in Internally
Flawless and Flawless diamonds, which take considerable examination
to assign such a high and valuable grade. It of course takes
longer to plot included diamonds as well.
Clarity
Grading Scale
What
is Eye-Clean?
"Eye-clean"
is a term used to describe a diamond or an inclusion that
is not visible to the unaided eye when the diamond is held
face-up (viewed through the table) at a normal viewing distance
of 10 to 12 inches. Nearly all VS clarity diamonds are eye-clean,
most SI1 clarity diamonds are eye-clean and some SI2 and even
I1 clarity diamonds are eye-clean.
An
inclusion is called "eye-visible" when it is visible to the
unaided eye, without magnification.
Types
of Clarity Characteristics
There
are two basic categories of clarity characteristics, inclusions
and blemishes.
Inclusions
are clarity characteristics that are completely enclosed in
a polished gem or those extending into it from the surface.
Examples of inclusions are as follows:
* Crystal — Another mineral crystal contained in the diamond.
These crystals can include other diamonds, garnet or a host
of other minerals.
* Needle — A long, thin crystal.
* Pinpoint — A very tiny crystal that looks like a dot or
speck of dust. Pinpoints often congregate in clusters or clouds.
* Twinning wisp — A series of pinpoints, clusters or crystals
that formed in a twinned diamond's growth plane.
* Internal graining — The appearance of faint lines, angles
or curves caused by crystal growth.
* Feather or gletz — A general term for any break or fracture
in a diamond.
* Bearded girdle — Minute feathers that extend from the girdle
surface into the stone.
* Indented Natural — The original crystal surface, or skin,
that dips below the polished diamond's surface.
* Knot — An included diamond crystal that extends to the surface
after polishing.
* Cavity — Space left when a surface-reaching crystal comes
out during polishing.
Blemishes
are external clarity characteristics caused by wear, the cutting
process or the diamonds crystal structure. Examples of blemishes
are as follows:
* Nick — A small chip-like characteristic.
* Abrasion — A series of minute nicks along a facet junction.
* Scratch — A thin, dull, white line across the diamond's
surface.
* Natural — A portion of the original skin that remains on
the diamond.
* Pit — Small surface characteristic that looks like a tiny
dot.
CARAT
WEIGHT
A
carat is a weight measuring unit equal to 0.2 grams. It is
the internationally used unit to measure the weight of diamonds.
Within the diamond trade, fractions of a carat are referred
to as "points" or simply as fractions. A 50-point diamond
weighs 0.5 carats or 1/2 a carat. A 1-carat diamond weighs
100 points. A 1/3 is also 0.3 carats or 30 points.
As
nature would have it, rough diamonds come in all shapes and
sizes, as well as colors and purities. The larger, whiter
and cleaner the diamond, the more rare it is. Accordingly,
the cost per carat of a larger diamond of the same color,
clarity and cut will be higher than a smaller diamond. The
price per carat of diamonds rises proportionately with size.
Keep in mind that the per carat price gets multiplied by the
carat weight.
More
weight equals more money so, many diamond cutters sacrifice
brilliance to maximize carat weight and profit. It is important
to realize that weight does not always equal size or beauty.
Poorly cut diamonds intended to maximize size can be dull
and lifeless. Some experienced cutters sacrifice weight and
focus on cut to obtain the most beautiful and brilliant Hearts
and Arrows diamonds on the market today. On the average, cutting
a Hearts and Arrows Diamond requires a 15% greater waste of
the original material. The added beauty one obtains from a
Hearts and Arrows diamond is well worth the sacrifice. Texas
Diamond and Jewerly specializes in sourcing these cutters
and bringing the most beautiful diamonds to you.
The
following is a chart indicating the average mm size per carat:
Carat
Approximate MM Diameter
