What is Diamond Clarity?

Because of their value and beauty, people take diamonds very seriously. The industry is massive, and professionals dedicate their entire lives to learning as much as they can about every aspect of these gems.

Of the many ways to appraise a diamond, clarity is one of the most involved.Carat, color, and cut – the other main factors – can be determined with a glance or simple instruments. Clarity, on the other hand, requires knowledge and a lot of experience to assess.

That’s why we wrote this article on the art and science of diamond clarity, giving you a look into the skill that goes into this importantgrading factor.

This should answer all the questions you want to ask about diamond clarity and give you an upper hand when shopping for your next piece of jewelry. Here we go.

Diamond Clarity Defined

Clarity is the assessment of the flaws contained on the surface or within the body of a diamond, and it’s one of the main factors in determining the value of a stone.

These flaws, also known as inclusions, may not seem like a big deal to the untrained eye, but in the diamond business, even a small speck or divot can knock a lot of money off the potential price. That’s why gemologists and jewelers use loupes and 10x magnification to examine the interior of every stone.

This assessment is a way to protect the consumer from paying too much for a diamond and ensuring that sellers get the value they deserve.

Appraisers and certifiers will draw from a wide range of reference points and past teachings to guide them to the right decision, taking their time to look over each stone. 

Once again, clarity is one of the 4 C’s of diamond quality, but many believe it to be the most important of them all. Cut is considered more of a subjective thing (do you prefer oval or emerald shape?), and carat doesn’t mean much if the diamond itself is filled with flaws.

Even color comes down to preference in the modern era, so it’s not a top priority.

Clarity, however, is pretty much the bottom line for diamond buyers, and just a few flaws can alter price in a big way. When ranking the 4 C’s, clarity always comes out on top.  

Clarity Grading Factors

The stakes are high when assessing diamond clarity, so jewelers need a universal language to stay on the same page. This is where grading factors come in and help us know exactly what to look for under that microscope.

The following grading factors are laid out for us by the American Gemological Society and serve as the standard by which all jewelers and appraisers follow in the United States.

Size refers to how large the flaws are within the stone. The bigger the blemish or inclusion, the bigger the impact it will have on the overall clarity scores. This also considers the size of the flaws relative to the size of the stone.

Nature is the type of flaw identified within a stone or on its surface. We’ll dive deeper into the different categories soon, but for now, know that internal flaws are referred to as inclusions, while surface-level features are called blemishes.

Number is the total sum of the flaws detected. This usually refers to the amount of easily visible inclusions, and fewer is always better.

Position is important because it tells us where in the stone the inclusion or blemish is found. Flaws located directly under the table of a diamond – close to the top looking down – are obviously a bigger problem than a small scratch deep within the body.

Relief, sometimes called color, refers to the contrast between the flaw and the material surrounding it. This plays a role in determining the severity of an inclusion. A very dark internal scratch or cavity will be more of an issue than a light flaw that is harder to detect.

Learn this lingo, and you’ll start to see how diamond graders operate.

Types Of Inclusions And Blemishes

You now know the main factors at play when assessing a stone’s flaws, but there is even more to the story. There are lots of types of inclusions and blemishes to look for, and jewelers use this lingo to communicate the flaws they find.

Certain flaws carry more “weight” when judging a stone than others, and some occur naturally while others are from human error during the extraction or cutting process. These small variations make a major difference in the final call.

A small impact mark on the surface of a stone is known as a bruise. This concussion can sometimes send crooked lines into the interior of the diamond and knock the rating down significantly. Larger bruises can even be seen with the naked eye.

The most common blemishes you’ll see are cavities and chips on the surface of a stone. A cavity is a clear, angular opening created by an unintentional chunk of material being removed. Chips are not as deep or severe but can also detract from overall clarity.

Blemishes sometimes stand on their own and can be confused as extra facets, but experts will be able to discern these mistakes from the intentional cuts. Surface markings often indicate a problem that lies beneath.

As far as inclusions are concerned, we’re mostly looking at shape, size, and contrast. A crystal is a small bit of matter within the stone itself, distinguished from the surrounding material. Knots are transparent crystals that make their way to the surface of the stone.

If you see a small grouping of tiny pinpoints within a diamond, that’s a cloud, which is not always mentioned in grading reports on lower clarity diamonds. It typically requires 10x magnification to see these small clusters of specks.

Elongated inclusions can be problematic since they extend beyond a single chunk or cavity. A needle is a best-case scenario here because it is short and thin, like a tiny rod. Feathers are worse, with­ fractures that extend further and sometimes reach the surface.

Finally, the twinning wisp is a series of individual inclusions that form a long strand of irregularity within. They usually move in unpredictable directions and can branch off.

These are the basic blemishes and inclusions you’ll hear about most often, but advanced jewelers also throw around terms that sound straight up crazy. Keep reading and researching to find out more about the shapes and types of diamond flaws.

The GIA Diamond Grading System

Broken down into six categories and 11 clarity grades, the Gemological Institute of America has been using the same diamond grading system since 1953. It goes into just enough detail to tell you what to expect at each level.

Entire books and courses are out there about this, but we’ll run down the basics of each category to set you on the right track.

Flawless (FL) diamonds have ZERO inclusions or blemishes and are incredibly rare. Fewer than 1% of all diamonds in the world earn this grade and have the price tag to match.

Internally Flawless (IF) diamonds may have some small surface blemishes seen under a microscope but contain no internal inclusions. To the human eye, flaws are undetectable.

Very, Very Slightly Included (VVS1, VVS2) diamonds have microscopic inclusions that can’t be seen with the human eye, even by the most highly-trained specialists. Under 10x magnification, these flaws are still barely visible.

Very Slightly Included (VS1, VS2) diamonds contain minor inclusions that may be easy to see under magnification, but under a loupe or plain vision are impossible to detect.

Slightly Included (SI1, SI2) diamonds have noticeable inclusions at 10x magnification but are still eye-clean. They are a fantastic value when buying big Cuban Link Chains andsimilar pieces with many thousands of stones.

Included (I1, I2, I3) diamonds will clearly show inclusions and blemishes; no microscope needed. Many retailers will not sell these items as a way to keep up standards of quality.


Diamonds are forever, so pick wisely and use clarity as a guide. Whether you’re going all-out on a big stone or you want some quality simulant diamond jewelry for your collection, this info will take you a long way.