Because diamonds form under tremendous heat and pressure, it is extremely rare to find a diamond with no internal or surface-reaching inclusions. Natural diamonds are the result of carbon exposed to tremendous heat and pressure deep in the earth.
Inclusions are a byproduct of its formation, and actually help gemologists separate natural diamonds from synthetics and lookalikes. The GIA Clarity Scale includes 11 clarity grades, ranging from flawless to I3.
Evaluating diamond clarity involves determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. If you are trying to determine what is the best clarity for a diamond, remember that no diamond is perfectly pure. But the closer it comes to purity, the better its clarity.
The GIA Diamond Clarity Scale has 6 categories, some of which are divided, for a total of 11 specific grades.
- Flawless (FL) No inclusions and no blemishes visible under 10x magnification.
- Internally Flawless (IF) No inclusions visible under 10x magnification.
- Very, Very Slightly Included (VVS1 and VVS2) Inclusions so slight they are difficult for a skilled grader to see under 10x magnification.
- Very Slightly Included (VS1 and VS2) Inclusions are observed with effort under 10x magnification, but can be characterized as minor.
- Slightly Included (SI1 and SI2) Inclusions are noticeable under 10x magnification.
- Included (I1, I2, and I3) Inclusions are obvious under 10x magnification which may affect transparency and brilliance.
Flawless indicates that there are no inclusions or blemishes visible at 10x magnification. A grade of I3 is for diamonds with inclusions that are obvious to the naked eye.
Diamond graders at GIA labs use a 10x magnification loupe and a microscope to see and plot the inclusions. Since no two diamonds are exactly alike, this unique plot helps identify a particular stone.
During this step, graders also look to see if there is any evidence that our diamond was treated to improve its clarity and any treatment will be noted on our diamond’s report.
Many inclusions and blemishes are too tiny to be seen by anyone other than a trained diamond grader. To the naked eye, a VS1 and an SI2 diamond may look exactly the same, but these diamonds are quite different in terms of overall quality. This is why expert and accurate assessment of diamond clarity is extremely important. Knowing what diamond clarity truly means helps you understand the factors that contribute to diamond quality and price.
How Did The GIA Clarity Scale Come To Be?
Like the color scale, GIA’s clarity grading system developed because jewelers were using terms that could be misinterpreted, “loupe clean” or “piqué.” Today, even if you buy a diamond somewhere else in the world, the jeweler will most likely use terms like VVS1 or SI2 to indicate the clarity of a diamond, even if his or her language is French or Japanese instead of English.
What Causes Inclusions?
Small crystals can become trapped in a diamond when it’s forming. Sometimes as a crystal grows, it can develop irregularities in its atomic structure. The size, position and visibility of inclusions can have a significant impact on diamond clarity.