Diamond clarity refers to the number, type & size of blemishes (or flaws) that exist in the gem. These blemishes are known as “Inclusions” in the world of diamonds. The more the inclusions, the lesser the clarity, the lower the price, the less attractive the stone!

A system was created to grade the clarities of the diamonds (under 10x magnification) by GIA. They graded the clarities by grouping them on a scale divided into six categories and eleven grades that we will see shortly.

Between the 11 grades, the SI1 (slightly included) is the most controversial of all grades. Some say that it has a lot of inclusions to the limit that you can identify with your naked eye, others -however- say it’s considered an eye clean grade! And some are in the middle! 

These two diamonds you see here are identical in terms of general characteristics (4Cs, polish, symmetry), they even both have SI1 clarity grade:

SI1 Grade Difference

Unbelievable, isn’t it?

Well, let’s now take a deeper look (20x or even 40x) at both of them, here is the first one to the left, and this is the one to the right, why the difference? If we figure out why, then we can definitely understand why the SI1 is a very, how can we say that, a problematic grade for many people!

In this post, we will be discussing everything you might want to (and as a matter of fact should) know about SI1.  We will be uncovering if it’s a good grade to buy in the first place, as well as when it’s okay to buy it and from where, when to avoid it, and when you will be making a good deal by getting one!

Why Higher Clarity Grades Are Insanely Expensive?

The end goal of all of this reading and researching is to help you in your quest of finding the right diamond for you or your loved one, and of course, for the best budget you set!

We believe that in order to make the best buying decision, you’ll need to be clear on the diamond facts that matter, and it requires that you have at least a basic understanding of the different types of diamonds on the market and their characteristics (4Cs).

While diamond market experts would easily tell you that the best diamonds are the flawless (FL) & internally flawless (IF) diamonds with no inclusions at all, they may not state that there are good diamond clarity alternatives other than the perfect FL’s and IF’s, and not even close to these grades!

Well, the diamond industry is a lot like the cars industry. For the same budget, you can find many options (with distinct specifications) and there’s an alternative for each option!

Imagine if you go to a car dealer and ask for a car that can just take you from home to work and vice versa, then they suggest you a brand-new Tesla! What would you think of the suggestion in this case?

This is EXACTLY the same when you ask for an eye clean diamond, and you get a suggestion to buy an extremely high clarity grade like flawless of VVS.

Look at this image, for example, this is an Internally Flawless True Hearts diamond on James Allen, priced at $30k, which is almost DOUBLE the price of the same characteristics for a VS2 difference (like this one):

Flawless TrueHearts

And even if you inspect it under the 40x superzoom or a 360-HD image that James Allen provides, you will not be able to detect any inclusion and that’s what flawless means.

Flawless and Internally Flawless diamonds are very rare; they both sum up to almost 3% of diamonds globally, and if that tells us something, it’s why they are extremely expensive in comparison with the other clarity grades!

But does this mean that to get a clean diamond, you have to step up to that level? 

This blog is designed for you to not feel regret after your purchase and most importantly to be rest-assured that you have done all the research that could be done to get the best option there for your budget!

Many people have had to ignorantly spend way higher than their normal budget, even when they could have gotten something that is at a lower price (and still a good option).

Although the best diamonds sometimes are worth investing your money in, yet, you could also get other diamonds with some imperfections that do not, however, spoil the fundamental expectation of what people want in a sparkling diamond, at all.

What is SI1 Clarity Grade? And Why it Attracted a Big Attention?

SI (1&2) in clarity grade stands for ‘Slightly Included’; the “included” part refers to the inclusions found on the diamond (again, under 10x magnification as per GIA definition), whether they’re visible to the eye or not.

When it comes to clarity grade, amount, size, and the types of inclusions determine if a particular diamond is SI1 or VS2.

The diamond clarity SI1 is recently becoming one of the most adopted diamond clarity grades. The diamond clarity category SI1 is confirmed to have clarity blemishes. Blemishes, however, don’t necessarily mean visible inclusions.

That’s why it’s even harder for a lot of people to tell if an SI1-grade diamond is a good choice; since there is no general rule for all SI1 diamonds.

Because the clarity levels of a diamond specimen are a great determinant of its aesthetic value and overall beauty, the question remains of whether the SI1 clarity category is a good option to buy becomes a really valid one.

Diamond Clarity Grades and Where the SI1 Grade Falls

As mentioned above, diamond clarity levels are categorized into about eleven individual groups as they appear in the clarity chart below.

And for the sake of getting to our point in this post, we will group them into two broad classes: Eye Clean and Visible Inclusions.

P.S. This is not an official grouping at all, it’s only for the sake of having a quicker and better understanding.

Anyhow, keep in mind that this grouping only makes sense when you’re considering the clarity of diamonds using the naked eyes only.

However, in order to obtain the original eleven groups, you will need to view the samples under the standard 10× magnification.


Note: SI3 level is not adopted by major certification labs like GIA. It was actually introduced by EGL for the sake of sellers and not buyers, read here how and why.

Back to our 2-category simple classification of diamond clarity levels, we have the following:

  • Diamonds without visible blemishes (Eye clean)
  • Diamonds with visible blemishes (Not eye clean)

Some diamond analysts and experts agree that it is always better not to go for diamonds with blemishes, like simply avoid them all! This really means ignoring more than 97% of diamonds on earth!

Diamond Sparkle James Allen

Diamonds with blemishes have reasonably reduced aesthetic appeal -depending on the amount of observed blemish- to the eye, in fact, the more blemish or less clarity on a diamond sample, the less value it would have in the market.

Therefore, it’s not really reasonable to restrict our diamond use specifications to the FL (because of a list of factors including the huge price traits).

The extra price difference you’re paying when getting a very high clarity grade (whether FL, IF, even VVS grades) is for something that you can NEVER tell (by just looking) at the diamond with the naked eye.

So, you can be saving yourself more bucks if you go a little lower in clarity grade. Let’s jump right into it and discover together which grade limit we can choose and would be a “safe” choice!

This is where diamond clarity classifications based on a clean eye view, comes to bear.

Why you Should Look for Eye Cleanness Rather than Clarity Grades?

If you set your mind on a 100% eye clean diamond, then you can safely get a VS2, but, if you don’t care about having visible inclusions (we doubt that), then SI2 will be the cleanest grade WITH visible inclusions.

In the middle, the SI1 exists.

This grade is in between VS2 and SI2; it’s neither eye clean all time (as we will explain later) nor has inclusions seen by your naked eye!  It is concluded that as long as the impurities cannot be easily seen by the naked eye, the diamond sample would still retain good aesthetics.

Diamond clarity SI1 (most of them to be accurate) falls under the “diamonds without visible blemishes” category, so this is an initial good sign.

Blue Nile Ring 2

The point here is that even if you place a superior clarity diamond side by side with an eye clean SI1 diamond, it’s unlikely to think that they’re not of the same clarity levels.

SI1 diamonds are the intermediate between diamonds with visible inclusions and those without. Hence, there may be several times where they’d appear with little visible inclusions too, but this is not so common.

The good thing about this clarity level is that its total inclusions ratio to the ones visible to the naked eye is significantly small and would not affect the diamond sparkle in any big way.

Consequently, SI1 diamonds might be a good option for you- if you’re on a moderate budget and still do not want to sacrifice the stone’s vital features: brightness and sparkle!

Also, read: Diamond Inclusion Chart – How it Affects Clarity?

How to Tell if an SI1 Diamond is Eye Clean?

Sometimes, the issue with the decision of buying diamonds based solely on clarity levels is the fact that you cannot always determine for sure if what you’re buying is actually true and fully complying with the stated specifications!

Don’t expect that there are no tricky sellers in the diamond market; who would smoothly pose diamond products of lesser clarity and claim them to be what they’re not.

When people lose money in the diamond trade and they wonder why, well, this is in fact one of the main reasons why.

How to Guarantee an Eye Clean SI1 Diamond?

Always look for a magnified image and a certificate. If you’re at a local store, don’t just look at the 50 cm-away diamond from your eye to determine cleanness, try and look closer.

Now if you see any inclusion with your eyes, no matter how small it is, look for the next diamond right away!

If you’re unable to see any inclusion, check its certificate; for GIA certificates (for diamonds with +1 carat), you will see this clarity section:

GIA Clarity section for VVS2 diamond

After you see inclusions’ locations on the certificate, try to find them with your own eye physically on the diamond itself, if you can’t then that’s a good sign.

Because it’s 99% here that you’re looking at an eye clean SI1 diamond (and that’s why we always recommend GIA certificates as a first choice).

However, If you’re in an online store like James Allen or Whiteflash then you’re covered, you have 360-HD images for diamonds, you can rotate the image, zoom in 20x (and on James Allen, you can even go 40x with Superzoom technology).

With these high-definition zooming features, you’ll be able to see the unseen! In 90% of cases, you will be able to see most inclusions on the diamond, but remember that you’re inspecting a magnified image.

To inspect the actual size and shape of the inclusion, zoom out until you feel you reached the real diamond size, and then try to see the inclusion!

Take a look at this diamond for example, it’s an SI1, looking good actually, but it has some inclusions that are easily seen under magnification, but do you think you can spot them with your naked eye? We doubt.

That’s why you should always get your diamond from a reputable store that gives you high quality images for the diamond.

This way, you can be 100% sure that you’re getting an eye clean SI1 diamond and that you got the best bang for your buck! (Without investing more money in something that you will not be able to tell.)

Where to Buy an Awesome Eye Clean SI1 Diamond?

While a lot of people prefer to see and inspect the diamonds live in the store, we still suggest the online approach!

Online diamond shopping also allows you to filter the exact specifications that you need based on your budget with 360 degrees real diamond photos and very high zooming.

You can say that online diamond stores are two steps ahead of brick-and-mortar retailers! Online stores took the competition to a whole new level, what local store would allow you to browse quarter a million diamonds to pick from?

James Allen does!

James Allen, Blue Nile & Whiteflash are definitely our top 3 choices when it comes to online diamond shopping for a lot of reasons beyond this post, but feel free to check it in our comprehensive guide on Where to Buy the Best Diamonds Online.

To put a little more detail, if you’re looking for regular diamonds and very wide collection to pick from, then head directly to either James Allen or Blue Nile since they hold hundreds of thousands of diamonds (literally).

If you’re not sure from where to pick among the two, here is a good resource for you: JamesAllen Vs. Blue Nile – Full & Detailed Comparison

And if you’re looking for a hand-picked premium diamond, then please meet Whiteflash, the home of A CUT ABOVE® premium diamonds, Whiteflash allows you to examine all their in-house diamonds with 360-HD images as well, using great imaging technology!

Read: The Superior Quality Diamonds Store Whiteflash Detailed Review!

Whiteflash 360 HD Diamond Videos 970x250 (1)

Other Important Factors When Getting SI1 Diamond

Another thing to consider when buying an SI1 clarity diamond is the dispersion ratio of the inclusions. SI1 diamonds would usually contain either or all carbon spots, clouds, feathers and pinpoints, etc.

All diamond clarity grades except the FL class contain these blemishes in various ratios. The more clustered the inclusions on the gemstone, the more conspicuous and apparent it becomes.

The inclusions in the SI1 diamond would -reasonably- become less visible if the inclusions are not gathered up all in one spot or close to the diamond’s table facet of the sample.

If you discover that the inclusions on an SI1 diamond are found just beneath the diamond table region, then you probably need to find another stone to buy!

Let’s look at an example, this diamond you see here:

SI1 eye clean with crystal

Eye clean? Yes of course.

Do we recommend it? No of course!

Although the minor inclusions on the table & facets won’t hurt, but if you look at 7 o’clock, you will see a deadly black carbon inclusion! And it’s one the worst inclusions you want to avoid in your diamond.

Besides all that has been mentioned, authentic ratings from such organizations like the Gemological Institute of America (GIA) or the American Gem Society (AGS), are some other important things to ask for.

In fact, it is recommended that you only accept a diamond clarity rating issued by either of these organizations or the few other alternatives like IGI (and better to avoid EGL certified diamonds).

If you’re shopping from an online store, make sure you’re provided with all-sufficient visual proofs that could help you confirm.

When SI1 Grade is NOT Recommended? The Carat Effect on SI1

In general, what you’re concerned about when determining your diamond clarity is defining the level of impurities and imperfections that are on a diamond sample.

For higher carat weights, sometimes it’s recommended to skip the SI1 and go directly to VS2; just to be on the safe side. This depends as well on the inclusion type and location on the gem.

However, if we want to make it more specific, we can say that after 1.3 carat, if your diamond has inclusions on its table facet (even if they are small), we wouldn’t recommend SI1 so, better to play it safe and get VS2 in this case!

This is because it is easier to spot the blemishes in a bigger diamond than in a smaller one, we’ve explained this in more detail in our exclusive Diamond Carat Chart Guide: How Weight Affects Size.

If you’re still in doubt and need to ask about a particular diamond, please feel free to contact us through the form below and you bet we will be glad to offer you help and consultation (for free)!

Going a level up to VS2 should be enough in most cases to guarantee eye clean diamond, why “most”?

Because the same thing we saw with diamonds above 1.3 carat applies as you’re going higher, if you’re getting a large diamond (+2 or 2.5 carat), then VS2 might not be sufficient, and you might need to go VS1!

Last thing here, you better watch out for retailers who will be trying to sell you on a very high clarity grade for the sake of a higher Carat, it should be the other way around.

Bottom Line: Is SI1 Clarity Good Enough?

In a nutshell, you should be all set to get any eye clean diamond, and as most SI1 clarity grade diamonds are eye clean, the only thing you need to make sure about is the existence of any imperfections beneath the diamond’s table facet.

The other point to keep in mind is that if you’re buying a large diamond, like more than 1.2-1.3 carat at least -in many cases and depending on inclusion type & location- some inclusions can be seen on larger diamond even if it’s SI1.

In the above two cases, you don’t need to exceed VS2 grade; since VS2 is eye clean in most cases. Why not all cases?

Because if you go beyond 2 carat, some VS2 might have visible inclusions actually, and in that case, you will need to go VS1!

You might ask, what if I’ve been saving up for this forever and I’m on a good budget, why shouldn’t I invest more in clarity? 

Well, If you have more money, spend it on the CUT, it’s basically, the most important factor in any diamond, then if you got more money, spend some on Color and then go for a higher clarity level!

Find the One James Allen

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