This is the second instalment of our series on the 4 Cs (Colour, Clarity, Cut, and Carat Weight) of diamonds. Part 1 covered colour. Today we’ll look at clarity.

The Basics

Similar to how diamond colour is a measure of the absence of colour, diamond clarity is a rating of the absence of inclusions and blemishes in a diamond. Inclusions are imperfections or flaws inside the diamond, while blemishes are on the surface.

You may be wondering – what causes inclusions? Flaws can develop naturally in the internal structure of a diamond as it is grows, or other small crystals can get trapped inside as it is being formed.

When a professional is grading a diamond for clarity, they’re considering the number, size, colour and position of all the flaws that are visible under 10x magnification. Ultimately, they’re determining how these flaws affect the appearance of the diamond. Inclusions and blemishes change the way that light passes through a diamond, which will hurt the brilliance and sparkle of a stone.

The less inclusions and blemishes a diamond has, the more valuable it is.

Diamond Clarity Rating Scale

The rating scale for diamond clarity is split up into six categories. These are, in order:

Flawless (FL)
A diamond with a Flawless grade has no inclusions or blemishes, even under 10x magnification. Diamonds with this kind of clarity are incredibly rare – less than 0.02% of diamonds are graded as Flawless.

Internally Flawless (IF)
An Internally Flawless diamond has no visible inclusions under 10x magnification, but might have very small blemishes (imperfections on the surface). Diamonds at this clarity rating are also very rare.

In general, unless you’ve been looking at diamonds under a microscope for years and years, you would never be able to tell the difference between a Flawless and an Internally Flawless diamond.

Very, Very Slightly Included (VVS1 and VVS2)
VVS grade diamonds might have extremely minor inclusions, but they are so small that only skilled diamond graders will be able to spot them under 10x magnification.

Typically, VVS1 diamonds have inclusions that can be seen from the bottom of the diamond (the pavilion). VVS2 diamonds have inclusions that can be seen from the top of the diamond (the crown).

Very Slightly Included (VS1 and VS2)
These diamonds have inclusions that can be seen when using 10x magnification, but these inclusions will not be visible with the naked eye.

Slightly Included (SI1 and SI2)
At this level of clarity grades, inclusions are easier to spot under 10x magnification. For SI1 diamonds, these flaws are still usually impossible to spot with the naked eye, but for SI2 diamonds it’s possible that the inclusions could be seen with the naked eye.

Included (I1, I2, and I3)
Once you’re into the I-grade diamonds, the inclusions are easier to spot with the naked eye and are quite noticeable. The brilliance of the diamond will start to be affected at this point.

GIA Diamond Clarity Chart - The Bench Jewellery Co

How Does Carat Weight & Cut Affect Clarity?

The bigger the diamond (more carat weight), the easier it will be to spot flaws. For diamonds smaller than 1 carat, clarity is less important than cut and colour in terms of overall diamond quality.

In terms of the cut of a diamond, brilliant-cut diamonds are better for hiding inclusions than step cuts.

How Do I Get The Best Value for a Diamond?

Now for some more tips about getting great value when buying diamonds.

When comparing VS1 and SI2 diamonds with the naked eye, you might not be able to notice any difference. Fairly often, inclusions and/or blemishes are essentially invisible to anyone besides a skilled diamond grader. Despite that, these diamonds will have very different prices based on their clarity grades.

The majority of diamonds that are sold fall into the Very Slightly Included (VS1-VS2) range. They cost less, but unless you’re looking at them with a microscope you won’t notice any difference compared to the higher grade diamonds.

If you’re more worried about the colour or cut of a diamond, look at stones with SI1-SI2 grades. If your diamond will be over 1 carat, try to stick to SI1. If it will be smaller than 1 carat, you can safely consider SI2 diamonds and potentially find some great deals without compromising appearance in a major way.

Those who are looking for larger diamonds at good prices may opt for I1 grade diamonds. There will be visible inclusions, but you will get great value if your primary concern is size.

That’s it for now – stay tuned for our next post where we’ll look at diamond cut.