The clarity of a diamond refers to how clear, or “clean” the diamond is. The more “clean” the diamond, the higher the price. Most diamonds have “imperfections” in them. The clarity scale is a measure of the severity of those imperfections or “inclusions” as it is known in the trade.

For example, a deep break in a diamond which is not that visible when you look at the stone face-up, could sometimes have a greater impact on the clarity of a stone, than a small black crystal which you can see very clearly face-up.

The following is the GIA Diamond clarity-scale:

FL-Flawless

These stones have no imperfections inside or on the outside of the stone under the magnification of a loupe of 10 power.

IF-Internally Flawless

These stones have no inclusions under a loupe with a 10 power magnification.

VVS¹,VVS²-Very Very Slightly Imperfect

These stones have very small inclusions which are very difficult to see under a loupe with a 10 power magnification.

VS¹,VS²-Very Slightly Imperfect

These stones have small inclusions which are slightly difficult to difficult to see under a loupe with a 10 power magnification.

SI¹,SI²-Slightly Imperfect

These stones have inclusions which are fairly easy to see under a loupe with a 10 power magnification, or visible to the naked eye.

I¹,I²,I³-Imperfect

These stones have inclusions which range from eye visible to very easily seen to the naked eye.

SI³

Outside of the GIA Diamond clarity scale is a grade you may have seen called SI3. The Rap Sheet, which is a Trade Publication, honors the SI3 grade which is given out by EGL, the European Gemological Laboratory. It is described as a split between the SI2 and I1 clarity grade.

How much does “clarity” affect cost?

The effect of all the different properties of diamond on cost is discussed in more detail in the cost section. For clarity, let’s take a typical diamond for an example, and see what happens when we take it through different clarity grades.

Let’s start with a 1.00 carat diamond of G color and SI¹ Clarity. If you move up to a VS¹, you will pay approximately an extra $1000 per carat. Move up to VVS¹, the increase will be approximately $700 per carat. Improve the clarity to IF and the increase will be approximately $700 per carat.

If you really want to see what the differences in the clarity grades look like under magnification, there is an excellent book by Gary Roskin called Photo Masters for Diamond Grading. It provides photographs and explanations of different Clarity Grades and the inclusions causing them.