| There are 4 main characteristics that determine the quality and value of a diamond. These are color, clarity, cut and carat. These are known as the 4C's in the diamond business. Anywhere in the world, diamonds are described using this language. | ||||||||||||||||||||||||
Color |
Clarity |
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| The Gemological Institute of American (GIA) has established
a color grading system. It is divided into 23 color ranges, denoted by the letters "D" through
"Z". Color is the one characteristic that determines a large amount of the diamond's value. Think
of an inverted bell curve. The finest colorless diamonds are on one end, the fancy colored
diamonds are on the other with the diamonds of increasing color in the middle. It is not possible
to determine the color grade of two stones that fall next to each other on the color scale unless
these stones are compared side by side. Since each grade you go up in color increases the value
of the diamond, the consumer should remember that near colorless diamonds begin with the color grade J on
the GIA scale. You can not determine the color with the naked eye at this grade level. Therefore, a
consumer could decide to trade off the value in color by accepting a slightly lessor color and
put that value in one of the other C's.
| Clarity is broken into 6 main grades with two to three subdivisions
within those grades. The top 2 grades do not have any subdivisions. Clarity actually refers to a
diamonds perfection. If there are flaws in the crystal the price for the stone is less. Most people
can not see an inclusion in a 1ct diamond until it gets to a clarity grade of I1 or I2. Most consumers
do not want to see any flaws in their diamonds when viewed with the naked eye. The grade of the diamond at which you
can not see anything with the un-aided eye are the SI1 and SI2 grades. The lower the number of a subdivision
the more expensive the stone even though the only difference may be the location of the inclusion. The consumer needs
to determine the amount of cost he/she wants to associate with the clarity. This can also be a trade-off with carat, cut or color.
Below is a brief chart of the clarity gradings.
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Cut |
Carat Weight |
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| The cut of the diamond refers to the porportions. A well cut diamond that adheres
to the proper angles for the best light distribution by the prism. For a diamond, the crown needs to be
cut at a 34.5 degree angle and the pavilion with a 40.75 degree angle and the rest portioned as shown
in the diagram below. This is where the consumer needs the help of a professional since the cut is
not easy to ascertain with the untrained eye. If you compare a well cut diamond with one not as well
cut, it becomes obvious. Well cut diamonds have a premium price since they take more time to cut from
the rough and there is more waste.
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Carat weight is based on the gem's specific gravity. Specific
gravity is the ratio fo the density of any substance to that of water at 4 degrees C. When we talk
about a gem's weight we are discussing how big is it's appearance and what does it weigh. Size has
to do with a gemstone's dimensions. A carat is 0.200 grams. A 5 carat diamon weighs 1 gram. For each
weight their is a high and low range to take into effect the dimensions of the stone. For example, a
1 carat diamond may actually weight betweeen .96 and 1.10. The table below gives a formula to get
a best estimate for each shape of a stone.
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