Understanding
Diamond Basics:
Before
you start looking for a diamond, you want to have all of the necessary
information that is available to you, because the more you know, the better
prepared you are to make decisions regarding your purchase.
LEARN
ABOUT THE FOUR C's - Cut, Color, Clarity, and Carat.
DIAMOND
CUT
Most
diamonds are cut round with a full 58 facets, and a good cut, or make,
has more scintillation, more sparkle. It is the work of a master cutter
that allows the diamond to be cut in such a way as to permit the maximum
amount of light to be reflected through the diamond, and that's a great
reflection on you. It is the cut that enables a diamond to make the best
use of light.

COLOR
GRADING
Most
diamonds have a slight hint of yellow and the diamond color
scale is based on the amount of yellow present in a diamond.
Diamond color is graded according to the GIA Grading Scale.
Grades are based on the amount of yellow that is visible when
viewed facedown through the pavilion on a white diamond color
card using daylight equivalent fluorescent light. Each color
grade is based on a very small range. When a diamond is color
graded it is compared using a set of master stones. Master stones
are a set of real diamonds that display a range of known colors.
It is extremely difficult to see the color differences within
diamonds, but master stones help graders distinguish between
one color and the next.
GIA
color-grading scale
As
you can see the color-grading scale ranges from D to Z. The
highest color grade and whitest stone available is a D color
diamond. This is also the rarest color grade, which translates
to a higher value. Colors E and F have no detectable color to
the naked eye and they fall into the Colorless category. Diamonds
in the G to J color range have a hint of body color and are
considered Near Colorless. The eye begins to detect faint traces
of yellow in diamonds that are in the J to M range. We typically
sell diamonds in the color range of D to J and occasionally
K.

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
Would
you be interested in taking a quick tour on "How To Buy A Diamond"? Click
the following link:
http://howtobuyadiamond.gia.edu/Tour_FrameSet.htm
Call
us with any questions.
(210)
737-2050.
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