Blog, Buyer's Guide

Diamonds: Clarity


Because diamonds were formed deep within the earth under extreme heat and pressure, they often contain unique birthmarks, either internal (inclusions) or external (blemishes). Diamond clarity refers to the absence of these inclusions and blemishes. Diamonds without birthmarks are extremely rare (IF stones make up less than 1% of the world’s gem quality diamonds, for example) and this scarcity affect a diamond’s value.

Using GIA’s International Diamond Grading System™, diamonds are assigned a clarity grade that ranges from flawless (FL) to diamonds with obvious inclusions (I3). The GIA Clarity Scale contains 11 grades, with most diamonds falling into the VS (very slightly included) or SI (slightly included) categories. In determining a clarity grade, the GIA system considers the size, nature, position, color or relief, and quantity of clarity characteristics visible under 10× magnification.

  • Flawless (FL)—No inclusions or blemishes are visible to a skilled grader using 10× magnification
  • Internally Flawless (IF)—No inclusions and only blemishes are visible to a skilled grader using 10× magnification
  • Very, Very Slightly Included (VVS1 and VVS2)—Inclusions are difficult for a skilled grader to see under 10× magnification
  • Very Slightly Included (VS1 and VS2)—Inclusions are minor and range from difficult to somewhat easy for a skilled grader to see under 10x magnification
  • Slightly Included (SI1 and SI2)—Inclusions are noticeable to a skilled grader under 10x magnification
  • Included (I1, I2, and I3)—Inclusions are obvious under 10× magnification and may affect transparency and brilliance

Gemologists normally use a 10x loupe to rate clarity. Did you know that most diamonds have some type of surface blemish that usually cannot be seen with the naked eye? You should make sure to purchase an “eye-clean” diamond whenever possible. This means that you cannot detect these flaws simply by looking at them. If there are flaws inside a diamond that will only be seen under 10x magnification, it matters less when making your selection…unless of course you want to buy an internally flawless (IF) diamond for idealistic reasons. Clarity grades of IF, VVS1, VVS2, and VS1 will ALWAYS be eye-clean. In contrast, I2 and I3 are never eye clean. Remember that inclusions visible to the eye will detract from the beauty of your diamond.

A few things to keep in mind:

  • VVS1 and VVS2 diamonds are hardly distinguishable. Inclusions are so difficult to see that only a trained gemologist can detect under a 10x loupe. The difference between the two clarity grades lies in the position of the inclusions. If flaws are seen from the pavilion side, it is labeled as VVS1. If it’s seen in the top half of the diamond, it is a VVS2.
  • With VS1, you can be sure that diamonds are always eye clean. You’ll only see tiny white inclusions when viewing under a loupe. And although VS2 diamonds display noticeable inclusions under 10x magnification, the flaws would be unnoticeable to your eyes. Diamonds begin to have visible inclusions from VS2 onward.
  • SI1 diamonds contain inclusions under 10x magnification, but such flaws may or may not be visible without a loupe. On the other hand, SI2 diamonds have inclusions that are easily seen under a 10x loupe and sometimes without one. These might be bigger, more obvious flaws, and dark inclusions as well.
  • With respect to inclusions, it is best to avoid diamonds with chips and dark crystals. Chips are easily seen and once the surface of the diamond has been damaged, it will probably chip again. Aside from affecting the visual appeal of a diamond, it also weakens its internal form. Black dots or carbon crystals are the most annoying flaws you’ll see because they’re simply unflattering to the diamond.
  • A diamond’s clarity features intensify as you go up in carat weight. So a 3-carat diamond will display more flaws than the 0.90 diamond even if both have the same clarity grade. Because of this, you should opt for a higher grade (VS2 and above) when it comes to bigger diamonds.

In summary, make sure that your diamond is eye clean and within or above the VS range no matter what inclusions it possesses. Remember that every inclusion imparts character. Diamonds are born with natural characteristics—these minute flaws are what make diamonds uniquely beautiful.

Sources: GIA
Sebastian Naturski