|There are four main criteria used
to describe the quality of a diamond, and they are generally referred to as the Four C's: Color, Clarity,
Cut, and Carat
.One might argue that the most important "C " of all is actually a
"B", Beauty. Although the independent gemological labs we use are renowned in
the trade, the most accurate and detailed description in the world is only a poor attempt
to put into words how beautiful a diamond can be. In addition to being familiar with the
four C's it is also important to make sure that the diamond you are purchasing has been
certified by one of the top independent gem laboratories. The two most widely trusted labs
among diamond professionals are the Gemological Institute of America (GIA) and the
European Gemology Laboratory (EGL). These reports will describe the four C's for you in
minute technical detail.
Clarity is an indication of a diamond's purity. It is the term used to describe quite
literally the clearness or lack of flaws in a diamond. All diamonds have some, naturally
occurring marks in them, which may or may not be visible to the naked eye. These are known
as imperfections or inclusions. In all diamonds, except the most rare, tiny traces of
minerals, gasses, or other elements were trapped inside during the crystallization
process. These are called inclusions, but are more like birthmarks. They are called this
because they are included in the diamond! They may look like tiny crystals,
clouds, or feathers and they're what make each diamond different and unique. Many of these
birthmarks are not visible to the naked eye. In fact, it is very rare to find a diamond
that is completely clean to the expert eye using magnification. The clarity of a diamond
is graded by how many, how big and how visible the inclusions are. The fewer and smaller
the inclusions, the more rare and valuable the diamond. Less than 1% of all diamonds ever
found have had no inclusions and can be called internally flawless (IF).
The following are abbreviations for terms that are used world wide to describe the clarity of a diamond:
IF,VVS1,VVS2: Internally flawless or near flawless. Impossible to extremely difficult to find any inclusions, even under 10x magnification. IF is Internally Flawless, and VVS1 and VVS2 are Very, very slightly included.
VS1,VS2: 100% clean to the naked eye, and moderately difficult to very difficult to find inclusions with 10x magnification. VS1 and VS2 are Very slightly included.
SI1, SI2, SI3: Should be completely to almost completely clear to the naked eye (eye clean) when viewed from the top. Fairly easy to find imperfections with 10x magnification. SI diamonds are Slightly included.
I1, I2, I3: Borderline eye clean to fairly easy to find imperfections with the naked eye. Very easy to find imperfections with 10x magnification. I1 through I3 diamonds are Included.
This is one of the most important of all characteristics, and among the hardest to judge.
All other factors being equal, a poorly cut diamond can be worth less than half the value
of a well made stone. The proportions of a stone as well as its polish and
precision of faceting determine how much of the diamonds potential fire and beauty
may be released.
Diamond cutters are paid to retain the maximum weight from rough stones. You will find poorly cut diamonds such as overly long or fat Marquises, extremely deep Heart Shapes and Emerald Cuts, and Ovals and Pear Shapes with big shoulders, or overly deep or out of shape Rounds. A poorly made stone tends to result in a higher yield (less waste) from the rough while a better made diamond wastes more of the rough. A well cut round diamond typically weighs only about 40% or less of the original weight of the piece of rough the cutter started with. This is why better cut diamonds and near ideal cut stones command a premium.
The way a diamond is cut will most certainly influence its sparkle, fire and brilliance, as well as its perceived size and even, to some degree its apparent color. In order to maximize the diamonds brilliance it must be cut in a geometrically precise manner. This means properly aligning the facets so light will enter the diamond and reflect back through the large top facet, or table of the diamond. Shown below is an example of how a finely cut diamond will reflect light.
Symmetry, polish, and faceting are the most noticeable features of cut, but also important are percentages for depth, height and angles. Light should enter and exit a diamond through the top facets. A cut that is too shallow or too deep reflects it through the bottom facets, and lets the light leak out of the bottom or side of the gem.
|CARAT WEIGHT: The standard unit of measure for diamonds and
other gemstones is the carat. One carat is equal to 1/5 of a gram, or 1/142 of an ounce.
The carat is also referred to as containing 100 points. Therefore, a 50-point
diamond weighs ½ carat, a 25-point diamond weighs ¼ carat, and so on.
The price per carat of diamonds can at times increase exponentially with size, due to the rarity of larger gemstones.
A one-carat diamond typically costs 3.5 to 4 times what an equivalent ½ carat costs, and the same goes for subsequent increases in size.
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