Complete Guide to the SI1 Clarity Diamond

Full Information to the SI1 Readability Diamond

Diamonds tell a story. When buying a diamond, you are looking for a gem that will be special enough to be part of your family’s history.

Diamonds are rated on their color, cut, weight and clarity. Most gems available in the market will have inclusions, and these inclusions make the gems unique and determine their clarity. A diamond with SI1 clarity is at the sweet spot of a good clarity rating at a more affordable price. 

What Is SI1 Clarity? 

Brilliant Round SI1 Clarity Diamond

SI1 clarity grade diamonds are stones with inclusions that can be detected using 10x magnification but not the naked eye. 

The clarity of a diamond is rated on a scale that ranges from I (Included) to FL (Flawless). Flawless diamonds have no visible blemishes and are extremely rare. Inclusions are identified with the naked eye and 10x magnification to grade diamonds. 

SI (Slightly Included) diamonds sit somewhere towards the lower end of the clarity scale. SI gems are divided into two categories, SI1 and SI2. SI1 stones have smaller and fewer flaws than SI2. The inclusions in SI gems are visible under 10x magnification but are not noticeable to the naked eye. 

It’s important to note that two SI1 diamonds can look vastly different. The type and location of the inclusion will determine the overall appearance of the diamond.

Is SI1 Clarity Good? 

Examining an engagement ring with a loupe

Yes. SI1 clarity is a good choice when looking for a beautiful stone at a more affordable price. 

When buying a diamond, it is more important to focus on the noticeable factors such as the cut and carat of the stone. Buying a gem with a higher clarity grade may not be worth it if you can find a lower grade diamond that does not have visible flaws. 

Most SI1 rocks will not have spots that can be seen with the naked eye. That makes it a good option because you can get an SI1 clarity diamond that looks just as good as a stone with a higher grade. A good example is the Sharpton Ring which has a 1.03-carat diamond with SI1 clarity. It’s hard to tell the difference between this diamond and VS2 stone.

Types of Inclusions in SI1 Diamonds 

Plotting Circles on Brilliant Round SI1 Clarity Diamond

There are two main types of flaws that affect the appearance of a diamond. The inclusion could be another mineral pressed into the diamond during formation or an imperfection on the surface of the gem itself. Smaller, lighter inclusions do not have as much of an impact on a stone’s clarity as large, dark blemishes do. 

SI1 grade gems generally have small spots that allow the diamond to look clean to the naked eye. It is not common for an SI1 clarity stone to have a prominent, centralized inclusion. However, more significant flaws may occur, resulting in a less desirable diamond. 

The large imperfection may also affect the durability of the stone. Diamonds may be the hardest minerals on the planet, but they can chip. Gems with a low clarity grade may have vulnerabilities that could cause the diamond to break. 

Best Value for Money 

Customer Trying on Vintage Engagement Ring on Finger

Different inclusion features have various impacts on the beauty and longevity of a diamond. While most SI1 diamonds may not have visible flaws, some might have blemishes that mar the gem’s appearance. 

At Estate Diamond Jewelry, we believe that VS2 (Very Slightly Included) clarity grade offers the perfect balance between the price and clarity. These diamonds are a clarity level above SI1, and their inclusions are difficult to spot with 10x magnification. 

With fewer flaws to worry about, a VS2 gem will look good and not have vulnerability issues. They can be cut into more shapes than SI1 diamonds as they have fewer flaws to be made visible by the cutting process. 

Where VS2 Sits on the Clarity Scale 

SI1 Clarity Diamond Side Angle

VS2 clarity is the lower VS (Very Slightly Included) diamond grade category, sitting almost in the middle of the clarity scale. Most VS2 stones have no visible imperfections. A trained eye can see their inclusions under 10x magnification, but the flaw’s location makes it difficult to spot. 

Blemishes found in this clarity grade are considered minor. Therefore, VS2 gems like the one set in the Altona Ring may look like flawless diamonds while costing significantly less than their unblemished counterparts. 

SI2 Clarity Diamond vs. SI1 Clarity Diamond 

Diamond Clarity Chart Infograph With Inclusions

The SI (Slightly Included) clarity grade has two categories; SI1 and S12. SI1 sits higher on the scale and has fewer and smaller inclusions. 

SI1 stones have flaws that can be seen under 10x magnification but are rarely visible to the naked eye. They are what is known as “eye-clean.” SI2 clarity gems, on the other hand, have imperfections that may be large enough to see even without the aid of a microscope. However, not all stones are created equal, and you might find an SI1 stone with a visible defect and a relatively clean SI2 gem. The location of the flaw will often determine its visibility. 

Blemishes in SI2 diamonds may be located on the periphery of the stone, giving the appearance of an eye-clean product. The flaw will probably be visible from the side so when buying stones in this grade, make sure to view them from all angles. An SI2 stone with inconspicuous inclusions is a better value for the money than an SI1 gem. You will get a clean diamond at a lower price point. 

Inclusions are easier to spot in larger carats. Therefore, if you want to invest in a large carat diamond, you would be better off going with an SI1 clarity stone. The flaws will be easier to conceal.

What’s the Difference Between SI1 Clarities and VS Clarities? 

Customer Looking at Large Diamond with Halo in Showroom with Afshin in Corner

SI1 clarity diamonds have inclusions that can be detected under 10x magnification but not with the naked eye. On the other hand, VS clarity stones have spots that are hard to see even when viewed with a 10x microscope. VS diamonds rate higher in the clarity grade scale than SI1 rocks. 

The diamond clarity chart goes from the least included to the most included stones, ranging from FL (Flawless) to I (Included). There are 11 grades within the scale, and an SI1 clarity grade falls on the lower end of the spectrum. 

Diamond Clarity Scale 

Diamond Clarity Chart

Flawless (FL) – Flawless diamonds have no visible flaws, even when inspected under 10x magnification. They also do not have any scratches on the surface that may mar their appearance. Flawless diamonds are scarce and make up only 2% of gems found in the market. 

Very Very Slightly Included (VVS) – These gems have tiny inclusions barely visible under a 10x microscope. It is hard for buyers to distinguish between an FL and a VVS stone. VVS diamonds are very clear and sell at a premium price. 

Very Slightly Included (VS) – VS stones are considered excellent diamonds, although they have larger and more numerous blemishes than the VVS stones. Their imperfections do not interfere with clarity, and flaws are difficult to spot with 10x magnification. 

Slightly Included (SI) – This is the level at which we begin to see more commercial-grade stones. SI diamonds have inclusions visible under a 10x microscope but are not likely to be spotted by the naked eye. These gems appear cloudier to graders with a trained eye but will probably look like higher clarity grade diamonds to the consumer. 

The SI level is split into two categories. SI1 stones have smaller and fewer blemishes than those grouped as SI2. 

Included – This is the lowest diamond clarity grade. These stones have blemishes that are visible even without the aid of a microscope. These inclusions can mar the appearance of the rock and compromise the durability of the gem. Diamonds in this grade are considered gem quality but may not be worth purchasing. 

How Are Clarity Grades Determined? 

Customer with Yellow Diamond and Loupe

Five factors determine how diamonds are graded on the clarity scale. These factors are size, nature, number, location, and relief. Let’s take a closer look at each of them. 


The size of an inclusion affects the clarity of a stone. More prominent blemishes increase the likelihood of being visible to the naked eye, thus marring the gem’s appearance. 


Nature speaks to the type of imperfection present within the stone. It could be crystals, other precious stones, or dust. Nature also refers to how deep the inclusion is located in the diamond. 


The number of imperfections in the diamond determines its clarity grade. As the number of flaws increases, the grade of the stone decreases. 


Location refers to where in the diamond the blemish is situated. If it’s at the center of the stone, it will be more visible, negatively affecting the gem’s appearance. Inclusions on the periphery are harder to see and can even be hidden by the prongs of the ring setting. Peripheral imperfections have a more negligible impact on the clarity of the gem. 


Relief describes how noticeable the flaws are compared to the stone. It is the contrast between the rock and the inclusion. A high relief means greater contrast and a more significant impact on the gem’s clarity. 

How Much Do SI1 Diamonds Cost? 

Shopping for a diamond engagement ring from Estate Diamond Jewelry

The price of an SI1 diamond will depend on the carat weight, cut, color, and type of inclusions within the stone. A one-carat, round-cut SI1 diamond in color grade G can range from $4,000 – $5,500. A 0.05 stone of the same clarity, color, and cut would cost $900 to 2,000. For a 2 carat SI1 stone, you may have to cough up $12,000 to $25,000. Round-shaped diamonds are about 20% to 40% more expensive than other cuts. 

SI1 clarity grade diamonds are a great choice when acquiring a beautiful stone at a more affordable price. It may be hard to distinguish an eye-clean SI1 gem from one of a higher clarity as it will not have visible inclusions. 

When SI1 Diamonds Are the Best Value

13025 Customer using a Loupe on a Diamond and Sapphire Halo Engagement Ring in Showroom

There are specific shapes that result in an eye-clean SI1 diamond. These shapes provide the best value for money as you will get a flawless-looking diamond without the hefty price tag. Take a look at the best cuts for SI1 clarity grade stones. 

Princess-Cut and Round-Cut Diamonds 

These shapes will primarily produce a stone without visible flaws. It would be best if the gem were two carats or less as imperfections are harder to hide with large gems. 

Pear Shape, Radiant Cut, Marquise, Oval Cut, and Cushion Cut – These cuts are the best at hiding blemishes. You can pick an SI1 gem with these shapes as its flaws are unlikely to be visible to the naked eye. 

Heart-Shaped Cut – A heart-shaped cut will hide inclusions in SI1 diamonds but not as well as other shapes. You might be better off opting for a cushion or oval cut instead of risking your stone by cutting it into this shape. 

Baguette, Emerald Cut, and Asscher Cut – These step-cuts show blemishes more than any other cut. Choosing these options for your SI1 gem would not be advisable as flaws are more likely to be revealed. 

When looking to get the most of your SI1 clarity grade stone, opt for a cut that is likely to hide its imperfections. That will give you the best value for money. 

Top 7 Insider Tips for Buying an SI1 Diamond 

Customer in Showroom looking at Diamond Engagement Ring on Hand

It can be challenging to understand why a 2 carat SI1 stone can cost $6,000 while another gem of the same clarity grade and weight goes for $20,000. When purchasing a diamond, it’s essential to understand the qualities that make it desirable to ascertain how much you should spend on it. These are some factors that experts recommend looking for when choosing an SI1 clarity grade diamond. 

Examine the Diamond Closely 

When viewing the stone, look for any inclusions that might be visible. This may not be easy to do online, but some sites offer high-quality photos and allow you to zoom in on the diamond to better see any blemishes that might be present. Some online stores like Estate Diamond Jewelry have home viewing programs to send the diamond to you for inspection. 

If there are visible flaws, note their size and location, which will help determine the piece’s price. With an eye-clean diamond, you should not be able to see any inclusions. 

Refer to the Clarity Plot 

Clarity plots are drawings that show the type of blemish a diamond has and where the flaw is located. These imperfections are detected by a qualified grader using 10x magnification. Diamonds that are one carat and above come with a lab report that includes the clarity plot. 

Clarity plots are like fingerprints. Every stone has its unique map of inclusions. Comparing the clarity plot to the physical diamond will better help you determine if the flaws are visible to the naked eye. 

Determine the Placement of Inclusions 

SI1 clarity grade diamonds have inclusions barely visible to the naked eye. An eye-clean SI1 stone is likely to have slight inclusions spread out. They are less likely to affect the gem’s clarity than larger blemishes grouped close together. 

Look for Minor Imperfections 

Inclusions add to a stone’s character and can even enhance its beauty. However, large blemishes prevent diamonds from reflecting light in the same way that a cleaner stone would. When dealing with imperfections, it’s advisable to source stones that have minor flaws. Tiny spots or cracks will not be as noticeable as dark crystals embedded in the rock. 

Understand Your Shape 

Some cuts hide inclusions better than others. For example, princess and oval cuts are more forgiving than emerald cuts. Step-cut diamonds like Asscher and emerald have broader facets that make blemishes more visible. If you are looking for an excellent SI1 diamond, it would be best to pick a cut that will likely give you an eye-clean stone. 

Authentic Certification 

GIA (Gemological Institute of America) and AGS (American Gem Society) labs have a reputation for being consistent and trustworthy with their certification. When an SI1 diamond has a certificate from either of these institutions, you can be assured of its quality. Authentic certification will also enable you to get a reasonable price for your diamond if you decide to sell it in the future. 

Focus on Visible Qualities 

It’s hard to tell the difference between a VS2 clarity grade diamond and one that is SI1 without the aid of a microscope. However, the difference in price for these two stones could be significant. Instead of focusing on a clarity grade, look for a stone with no visible flaws. You will get more bang for your buck if you buy a gem that has a low clarity grade but is eye-clean. 

Talk to a Diamond Expert and Get a Quote

Shopping for a diamond engagement ring from Estate Diamond Jewelry

Many varying factors determine the value of a diamond. Diamonds vary in price depending on their cut, color, carat weight, and clarity. Two stones could look the same to the naked eye and have a difference in the price of up to $20,000. 

With so many factors to consider, purchasing diamonds can be confusing. When looking for an engagement ring or high-quality diamond, reach out to the experts at Estate Diamond Jewelry. They will guide you through the process and ensure that you get value for your money. 

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