Diamonds are the most popular gems. They have great brilliance and you often hear people talking about a diamond's fire. That's a diamond's ability to take in white light and throw back flashes of color.
Diamonds are graded into dozens of categories. While this is helpful to the professional, it can be confusing to the average consumer. At Accent Jewelers, we understand and we're here to help. First, we'll explain how diamonds are graded, and second, we'll give you some ideas to consider when you're buying a diamond.
Diamonds are graded on four qualities, commonly known as the 4 C's:
The closer a diamond is to being colorless, the greater it's value. When the current grading system was introduced in the 1930's, diamonds were commonly called grade A, B, or C. So the current system began color grading with the letter D, to avoid any confusion. Colors D, E and F are the highest grades. They are described as colorless. Colors G, H, I and J come next. They are described as near colorless or white. The colors from K to Z are tinted, (usually yellow or yellowish brown.) Those that are just lightly tinted, K, L and M are often said to set white. That means that they are so lightly tinted that they will appear white if set in yellow gold. You would notice their color if they are set in white gold or platinum. As you get further down the alphabet, the tinting gets stronger and the value lower, until you get to the extreme. As the color becomes richer, you have a fancy colored diamond, rather than an off colored one. Then the value starts going up again.
The clarity of a diamond is determined by the size and number of inclusions inside of it. An inclusion can be another mineral, a fracture or occasionally a void. Simply put, it is anything that will interfere with the free passage of light.
Just like with color, there are many clarity grades. They are judged by what an expert can see at 10 power magnification, under ideal conditions. The highest grade a diamond can get is Flawless. That means no inclusions can be seen at 10 power magnification. It does not mean inclusions can't be found with higher magnification, nor should you assume it is the only grade with no inclusions visible to the naked eye.
Clarity grades use the letters V, S and I. They stand for Very, Small, and Inclusion. Progressing from Flawless, the grades are VVSI1, (Very, Very Small Inclusions One,) VVSI2, VSI1, VSI2, SI1 then SI2. These are the grades of diamonds that have no "eye visible" inclusions, those that can't be seen with the naked eye. As we progress down the grading scale, there is I1 and I2. These have eye visible inclusions, but are still considered to be gem grade. Grades P1 & P2 are not usually considered gem grade because so little light will pass through them. However, since they have the magic name diamond, they do show up on the market regularly. Beware of ads that say "one carat diamond ring, $299." Just because something is a diamond, doesn't mean it is a gem. In fact, the vast majority of diamonds mined are usually considered "industrial grade" and are used as abrasives. Many of these "industrial grade diamonds," those graded as P1 and P2, find their way into jewelry simply because they had the advertising appeal of being diamonds.
This one of the hardest properties to judge, plus there are a number of factors to consider. There are no grades for this. Most jewelers are familiar with correct proportions and can judge it from the shape. The best test for most of us is to simply compare the gems side by side. If you have two diamonds of the same grade and one is significantly brighter than the other, the cut is the difference. Another factor that comes under the heading of cut have to do with the shape of the gem. An ideal cut gem should be symmetrical, not lop sided.
This is by far the easiest of the factors to understand. Simply put, smaller diamonds are more common than large ones. Therefore smaller diamonds cost less per carat than large ones. If you were to see a diamond broker's price list, under each grade, the price per carat would go up with size. A grade of diamond that would cost $900 per carat in the 1/2 carat size might cost $1100 per carat at 3/4 of a carat and $4000 in a full carat.
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