Summary in a few lines:
Diamonds inclusions are small imperfections in diamonds, happen as a result of extreme heat & pressure the diamond get when formed.
Inclusions aren’t necessary bad, most of them are “okay” to be in a diamond depending on size & location, but some are NO-GO and indeed should be avoided.
Diamonds with no inclusions are very rare, on James Allen, out of 520k diamonds, only 7k are flawless or internally flawless (flawless only are even lower, 240) as you can see in this search (less than 1.5%), the same (almost) goes for Blue Nile, with 10k out of 510k diamonds!
Some of the worst inclusions to be avoided are Black carbon spots/crystals, Long fracture/cracks, Knots, Clouds, and in terms of position: inclusions in the diamond table center.
What are Diamond Inclusions (Flaws)?
Many consider freckles to be beautiful. Some would go out of their way and say sexy! They’re rare, unique, attractive, and make you definitely look younger!
No, you’re not in the wrong place, this blog is still about diamonds, lol!
In the world of diamonds, birthmarks are considered imperfections (inclusions) that are found on diamonds, for the sole reason that they are formed under intense conditions.
Under 100 miles deep, and a 2,000 Fahrenheit temperature, with an exerted pressure of more than 70,000 pounds per inch square (too much physics!), a diamond with some flaws (on its surface) will definitely be made! These imperfections are called “Diamond Inclusions”.
These imperfections cause the diamond to be unique and one of a kind because none of them is completely identical!
How Inclusions Look Like?
As a matter of fact, there are many diamond inclusion types. For instance, the image you see here is for a diamond with an SI2 clarity grade on “Blue Nile”, that diamond actually has 6 diamond inclusion types!
If you take a look at the GIA certificate of that diamond, and in particular its clarity section, what you’ll see is a clear representation of all clarity inclusions found on the diamond, their locations, and types as well!
Having all these inclusions, a valid question is: Is this a diamond that I should pick or avoid?
Well, it’s 1.5 carats and considerably cheap for that carat & excellent cut, but with all these visible inclusions, we don’t think so!
Hmm, you mean I should always look for a flawless/internally-flawless diamond?!
Definitely no, actually we always recommend to start with SI1 clarity for most cases, read more why.
Want to see how a diamond with clear clarity looks like without going insane in clarity grade? Say no more!
Check this diamond on James Allen’s site, looks way better! And it’s just VS2 graded.
And here is its clarity section from the GIA certificate:
Huge difference, right?
That diamond has a VS2 clarity grade, which is just one grade higher than SI1!
You see the value of getting & checking the diamond certificate before proceeding with the purchase! And make sure that the certificate is from high-reliable labs like GIA.
That’s why we always considering James Allen, Blue Nile or Whiteflash when you’re getting a diamond, they provide diamonds certification on spot for any diamond you want.
Ok, but are all inclusions bad?
Sure no, and you don’t have to avoid them all when shopping for a diamond! Some inclusions (as we will see shortly) are absolutely okay to be in a diamond.
To make a clearer point, there are inclusion types that affect the total clarity, while others are much less harmful (if any) to the appearance of a diamond.
Diamond Inclusion Types (And Which Should be Avoided)
Based on the shape and structure, certain names have been given to the diamond inclusions. And of course, some should be avoided more than others!
Crystals inclusions are basically a collection of small diamonds or minerals trapped inside a larger one during formation. They can either resemble a diamond within a diamond or can resemble bubbles.
They appear in many colors: White, black, colored, and sometimes even transparent (colorless) crystals. Some of them are so tiny they’re invisible to the unaided eye.
It is easy for the white to blend in, however, the black and the transparent will definitely be popping out! The darker the color, the more you need to avoid; since it will have more effect on the diamond’s brilliance.
A rule of thumb would be to try to avoid any and all colored crystal inclusions.
Here is a diamond from Blue Nile with a crystal inclusion on its table facet:
This would be one of the most common diamond inclusion types that you’ll see while shopping for your stone! Needle inclusions are usually seen under magnification as it’s not easy to detect them with the naked eye.
When diamonds are formed, the pressure could transform crystals into needle-like shapes (clustery). They usually have a white color or are just transparent.
Despite the fact that diamonds are the strongest stone on earth, long and deep needle inclusions can (and will) weaken your gem; making it more vulnerable and less-harder to break!
Here is a diamond with many needles. You can notice that they’re pretty hard to spot.
Also, check out this diamond; which has a clearer needle on the table facet. Keep in mind that this is a 20x magnified image and that this inclusion is most probably not visible to the naked eye:
In most cases, needles are okay in diamonds, you shouldn’t worry about them as long they are not too deep or too long.
These are very tiny inclusions and can barely be seen under magnification. They appear as white dots and can be either white or black. This inclusion is considered diamond-friendly and doesn’t have much effect on diamond clarity.
The image here shows a pinpoint:
As you can see, it’s very small and won’t have “almost” any effect on the diamond, it’s safe to get diamond with such tiny pinpoints.
Clouds are sometimes referred to as a group (cluster) of pinpoints or crystals. It’s called a cloud when these pinpoints are very close to each other so that they form a “cloud” of inclusions.
They are not usually visible, however, if they are bigger, they might start to appear a bit cloudy or hazy; affecting the appearance of the stone and its light performance (therefore its sparkle!)
This diamond has 4 clouds on its table & crown facets, they might not be easily located before taking a look at the GIA certificate:
5. Twinning Wisp
Usually, the twinning wisps are found in fancy-shaped diamonds. The larger the-wisp, the lower the clarity.
A Twinning wisp looks a lot like stretch marks on a gem. It’s a bit different from the cloud inclusion in that it’s a series rather than a group of pinpoints/crystals (it even can be a series of clouds as well). It’s been said that is caused by a pause during diamond formation and the resumption of which leaves the gem dented.
Here is a diamond with 4 twinning wisps on Blue Nile.
Generally speaking, what applies to clouds applies to twinning wisps as well, if they are large, it’s generally recommended to be avoided.
This is a definite NO when it comes to diamond inclusion types!
Knots can actually be seen with naked eyes and they affect the durability of the gem. These are inclusions that have reached the surface area of the gem. It’s also worth mentioning that knot inclusions extend to the surface after fashioning.
This inclusion is named after its shape. It is basically an internal crack inside the gem. If the crack is located cleanse to the girdle area, it could cause serious durability issues! It’s better to be avoided if it’s large in size or reached the surface. Affecting the diamond clarity is not the big issue here!
Feathers are often white and feathery (hence the name) in appearance. This diamond on Whiteflash has two feathers right in the middle of its table, a bit to the left if you see them (you can see a magnified image on the website, just click the image to follow the link):
An opening on the edge or the surface of the gem; caused mostly by the wear and tear of the ring. Chips can be regulated by cutting and reshaping. However, in case the chip is considerably large, cutting could affect the carat (weight) of the gem.
This type of inclusion is less common to be seen since most of it can be treated in diamond cutting process, and if any, it won’t have much harm to the diamond appearance & brilliance.
This is an angular opening/hole in the center of the stone. Such inclusions are created when part of a feather breaks away, and sometimes when a part of a surface-reaching crystal drops out. However, cavities are rarely noticeable.
A blow to the surface of the gem leaves bruises that extend inside. Diamonds are quite fragile in spite of this inclusion.
Bruise inclusion is less common among diamonds, and probably you won’t come across one while shopping for your diamond, but still, if you find a diamond with a bruise, watch out for visible/large ones; because it’s that type of inclusion you want to avoid in your diamond.
Beard-hair inclusions (known as bearding) often occur in the cutting stage of the diamond. Whilst it can be ignored when tiny, it sure can’t be overlooked if the girdle is heavily bearded!
Its appearance will look grey and fuzzy fringe, almost as if it has been scratched. Not a good look on a diamond!
12. Indented Natural
Last but not least, the portion of the rough diamond’s original surface which can’t be fixed with the polish (since it dips below a polished diamond’s surface) is called “Intended Natural”.
This diamond on Blue Nile has 3 indented natural diamonds as you will see in the certificate. These inclusions are extremely tiny that they’re almost invisible even under 20x magnification, so generally-speaking, intended natural inclusions are okay to be in a diamond.
These are the main inclusions types that you might come across while browsing for your diamond. Just looking at the diamond itself isn’t enough. You MUST read the certificate to understand what types of inclusions the diamond has and how they affect its clarity!
P.S. The clarity section in the GIA certificate is only available for diamonds with 1 carat and above. We’re mentioning this so that you won’t be surprised if you don’t see a clarity section in your GIA certificate!
What are the Worst Inclusion Types to Avoid?
We’ve seen the different types of inclusions, and at this point, we know that they have different effects on the clarity grade, and on the diamond’s ability to reflect and interact with the light sources in general!
But in a nutshell, here are the worst inclusions to be avoided, graded with No.1 being the worst:
1. Black Carbon Spots / Crystals:
The light passing through the stone will be literally blocked (in the exact spot of the black crystal). These inclusions will look like tiny pieces of crushed black pepper.
These are the worst inclusions; you wouldn’t want them anywhere on or underneath the surface of your diamond for that matter.
Remark: Note that we are only talking about black-colored crystals.
2. Top / Center-Located Inclusions:
Generally speaking, any notable inclusion located on the top or in the center is quite harmful to your gem!
Look at this diamond on James Allen’s and check out the inclusion located in the middle. This location specifically is such a killer of a diamond’s brilliance. (This diamond has many other visible inclusions as well, but we wanted to highlight how important the location of inclusion is).
Whenever you’re looking for a diamond, just try your best to get a clean top-surface diamond (diamond table).
3. Long Fracture / Crack:
Have you ever imagined that a diamond is breakable? What about the 10/10 grade of strength on the Mohs Scale of mineral hardness?
The diamond has a short needle? Not a big deal. However, a long/deep needle/crack is a serious issue; as it runs all the way through the diamond!
Slamming such diamond to a wall too hard might also crack it (or even split it into halves!). It’s rare and totally dependent on the crack depth and length as well.
If you look right through this diamond; 6 o’clock sharp, you can clearly see a long crack. Not too long to break a diamond, but definitely an inclusion you’d want to avoid!
Back to our clouds! Small clouds? Those we can ignore. It’s the cloud covering a big portion of the diamond’s surface that we can’t! Leaving the diamond looking hazy and milky. Clouds affect the look, and more importantly, the brilliance of a gem.
Look at this diamond in 360-degree on the Blue Nile. Also, a screenshot of its clarity section on its GIA certificate as well.
It’s not only that the cloud is covering a lot of space on the diamond surface, what’s worse is the location, right in the middle of the table facet.
It’s always a NO-GO when the diamond has a knot inclusion, it can really get worse by time so even if it minor, it might be more visible by time.
How Inclusions Characteristics Affect Clarity Grading?
Remember our talk about freckles? Sometimes gems with inclusions are purchased specifically for their inclusions; as a source of beauty. Most inclusions, however, affect the gem’s clarity or grading.
By now, we know for a fact that not all inclusions are equal, but beside the type, what are other factors that should be taken into consideration when assessing an inclusion?
First comes the inspection (under 10x magnification; since inclusions are mostly visible under magnification), then comes the grading of the gems. The size of the inclusion has a huge impact on the grading.
Larger inclusions lead to lower grading, and vice versa. This totally makes sense actually, since eye-clean diamond (VS2 for example) will not have any inclusions that you can see, whereas the same exact inclusions (if existed) with a larger size will probably make the same diamond an SI1.
Numerous inclusions in a gem leave it unattractive as well as affecting its grading.
Low relief means that the inclusion’s color is close to the stone’s color. Therefore, inclusions like crystals that are translucent or white have less impact on the gem than dark ones.
Various types of inclusions impact the clarity and the grading of a gem in various degrees. For instance, pinpoints have a lesser impact because they are barely visible (even under 10x magnification). Other inclusions like feathers can have a greater impact as they could cause a gem to crack.
The location of the inclusion matters! Where the inclusion is situated in the gem goes a long way in grading, look at this image for example:
If an inclusion is at the table facet, it is the most visible of all and generally affects how the gem is seen (since the table facet is like the mirror of the gem), also it is the first place considered when looking at a gem.
When located at the girdle, it is rarely visible. Inclusions at the culet are another story! They reduce the value of the gem tremendously given that they can reflect throughout the whole gem.
How Inclusion Location Affects Clarity Grade?
Look at these two diamonds on Blue Nile and their clarity section in the image after:
And particularly on diamond 1 lower girdle facet (bottom right at 5 o’clock), you will see there is a small inclusion there, and on the keys section, it will tell you that this inclusion is Cavity.
This inclusion type & location degrades the clarity and the grade of the stone to SI1, but it’s not the only factor causing this step down!
The inclusions found on the very first image to the left (crown of the 1st diamond) are located at the worst location in a diamond (look again here using 360-degree, it’s easily visible).
In many cases, they will be seen by naked-eye, and more importantly, they hugely affect the diamond’s brilliance since light passes through the crown first.
In a nutshell, inclusion location is very important to determine clarity grade and overall brilliance, always look for a diamond with less or no inclusions on the top, or on the girdle (and its upper/lower facets).
Do All Inclusions Have the Same Weight / Effect?
In conclusion, not all inclusions are the same, and they sure don’t have an equal effect on diamonds, some are worse than others! And in some cases, a diamond graded as SI1 or SI2 might be a VVS if it doesn’t contain a certain inclusion (depending on the type and location).
If you look back at the last image above, both diamonds are SI1 clarity-graded, but if you look at the GIA certificate for both of them, you can see a huge difference in the number of inclusions found on each one.
P.S. Both stones have excellent polish!
The first one has around 9 “tiny” inclusions on its crown, and this is “relatively” a low number of inclusions, yet it was graded as SI1 not higher!
The second one has tons of inclusions all over its crown! And it was graded SI1, the same as the first one. Why is that?
Basically, because each inclusion impacts the gem differently. As we said before, no two inclusions are identical. Some can really harm the diamond’s brilliance; messing up its ability to reflect the light, others don’t.
Quick Overview of Clarity Table
Clarity is one of the 4Cs of diamonds and considered one of the main pillars in specifying a diamond worth. Clarity is graded into 6 categories based on the cleanness of a diamond.
We’ve covered the detailed grades with real images in our Diamond Clarity Chart, but for the sake of summarizing, we’ll mention the grades below:
Diamonds graded FL have no inclusions or blemishes visible to the eye at 10x magnification. These diamonds are extremely rare and are very expensive. Only 1 in 5000 diamonds are rated flawless.
These are diamonds that do not have inclusions but only blemishes. These blemishes are barely visible under 10x magnification. Only about 3% of diamonds are ever rated IF and if put side by side with FL, they are quite similar to the unskilled eye.
Very Very Slightly Included
Even at a 10x magnification, inclusions in diamonds here are still difficult to see. For VVS1, inclusions can only be seen from the pavilion while for VVS2 diamonds, their inclusions can only be seen from the crown.
For both, the inclusions are of course not visible to the naked eye and look similar to the flawless grades. These diamonds have clarity and are equally expensive.
Very Slightly Included
These are considered minor inclusions. They are very visible under 10x magnification, however, they’re not visible to the naked eye. Their slight inclusions do not affect the clarity or the transparency. These gems are categorized into VSI1 and VSI2.
This grade contains diamonds having visible inclusions (under 10x magnification). Some of them are also visible to the naked eye when examined under close inspection. They are divided into SI1 and SI2 gems (EGL introduced SI3, but it’s not internationally adopted).
Diamonds under this grade have inclusions that are obvious under 10x magnification. The inclusions are always visible to the naked eye and might even affect the durability of the gem. They also reduce transparency and the brilliance of the gem. They are divided into I1 through I3, don’t ever get any of them!
You can also read: What is the Best Budget-Friendly Diamond Clarity?
Inclusions Effect on Diamond Pricing
After all that’s been said, it would be safe to mention how these inclusions (which define the clarity grade for any diamond) affect diamond pricing.
Comparing an apple to an apple, we will be freezing our search to these characteristics, and then see how changing the clarity level affects the pricing in each!
Polish & Symmetry: Excellent
We will use our favourite online store James Allen as a price reference; as it has one of the largest diamond inventory and more than 500,000 unique options for diamonds!
Regardless of how much money you have and find reasonable for the price of your ring, we recommend going online and definitely believe it’s a responsible decision! The savings are incredible and the quality is great. You can check one of our favourite online stores: James Allen, Blue Nile, and Whiteflash.
Average Price for 1 Carat Diamond: SI2 Clarity Grade
After running a search on James Allen’s with the above-mentioned characteristics, the result was 47 diamonds, with prices ranging between $3.8k and $5.3k.
Average Price for 1 Carat Diamond: SI1 Clarity Grade
This search on James Allen’s with the above-predefined filters resulted in 77 diamonds, ranging between $5.2k to $6.4k.
Note the huge increase in price (for just one grade in clarity). That’s simply because SI2 is not eye-clean in most cases, while SI1 is the exact opposite, eye-clean in most cases.
Average Price for 1 Carat Diamond: VS2 Clarity Grade
A similar search here, returned 77 diamonds as well, from $6.4k to $7.5k.
Again, a huge increase in price. Think about it for a second, people resort to VS2 to stay safe in terms of visible inclusions; since it’s 100% eye clean. But does this change with VS1?
Average Price for 1 Carat Diamond: VS1 Clarity Grade
We got 46 diamonds, prices varied between $6.9k and $7.9k. As you see, the price difference is reasonable for 1 grade in clarity, that’s because both VS grades are eye clean.
Average Price for 1 Carat Diamond: VVS2 Clarity Grade
30 diamonds, with a price range of $7.3k and $8.3k; which is also a reasonable price in comparison with VS1.
Average Price for 1 Carat Diamond: VVS1 Clarity Grade
38 diamonds, ranging between $7.9k and $8.8k, also a reasonable price compared to VVS2.
Inclusion <> Price Correlation Summary:
In short, a jump from visible inclusions to eye clean diamond is the most expensive one in terms of clarity (as we saw from SI2 to SI1).
And with people preferring to stay away as much as possible from visible inclusions, price has also stepped up tremendously going from the recommended level SI1 to VS2.
Price Jumps of around $500 between higher grades are considered somewhat reasonable.
When you’re set on getting your diamond, watch out for the inclusions. Nonetheless, keep in mind that inclusions can only be visible where the gem is loose.
However, when the gem is in its setting (mounting style on the ring; holding it in place), grading might be difficult; since the setting (prongs or bezel) might be covering the inclusions somehow! This could also be a good thing when deciding to purchase a gem with inclusions. The setting could be made to hide the inclusion.