What are SI Diamonds?

An SI-grade diamond is a good recommendation for people who want to buy a beautiful-looking diamond at a low price. Their low price and unique ability to hide inclusions make SI diamonds very popular amongst diamond lovers. 

SI diamonds have flaws. However, the good thing is that these flaws are not visible to the inexperienced eye. Those who are not in the diamond trade will not be able to make out the impurities. Therefore, if you are looking for a bigger diamond but are on a budget, SI diamonds may be a perfect fit for you!

To learn more about SI diamonds, give this article a read!

What is an SI Clarity Diamond?

Diamonds come in different grades that are determined on the basis of the four Cs of gem grading: carat, color, clarity, and cut

Clarity represents how light passes through the stone. Clarity ranges from “Flawless” to “Included” with grades like F, IF, VS1, SI1, SI2, and so on. The scale runs from Flawless (F), which indicates perfect clarity and no impurities, to included (I), which indicates impurities that you can see with your eyes. 

SI stands for “Slight Inclusions” which can be noticed when you view the diamond at 10x magnification. Most of these diamonds have centered inclusions but these can vary from diamond to diamond. Within SI, there are two ranges: SI1 and SI2. SI1 has less noticeable inclusions than SI2. However, these inclusions do not degrade the quality of your diamond.

SI diamonds appear flawless to the naked or inexperienced eye. If you are concerned about visible imperfections, you should buy an SI1 diamond. However, you can also find SI2 diamonds with nearly zero visible imperfections, which makes them a great choice!

Overall, the SI clarity grade is perfect for people who want to buy a diamond but are on a budget!


Are SI Diamonds Real?

Yes, SI diamonds are real and very much in demand!

Even though SI diamonds aren’t flawless and are not on top of the clarity grade chart, they are still considered highly valuable.

Some people may have second thoughts about buying SI diamonds because they could be confused about their quality, as SI diamonds come with inclusions and cost 10% to 20% less than VS diamonds. 

Let me clarify that apart from an expert with years of experience, no one would be able to identify the inclusions on your SI diamond. It is a high-quality diamond that you can buy on a budget.

However, if you are still worried about the inclusions and visible imperfections, you should opt for an SI1 diamond, because in this range, inclusions are not outwardly visible. 

Does SI Clarity Affect Carat Weight?

Since the SI range of diamonds is not the highest clarity grade, some customers may think it will have a lower carat weight. There is a misconception that the higher the carat weight of the diamond, the better the quality and hence the clarity. 

This is, however, far from true. 

In reality, the SI diamond’s clarity has little to do with the carat weight of the diamond. However, the carat weight may, in some instances, affect the price of any diamond regardless of clarity grade.

SI1 vs. SI2 Diamonds: Differences 


An SI1 diamond has very few inclusions, making them difficult to spot by a naked eye. They can, however, be spotted under 10x magnification. 

In other words, experts can easily spot the inclusions on an SI1 diamond. However, the inclusions are so slight that they usually go unnoticed by most people. The inclusions in SI1 diamonds, when compared to SI2 diamonds, are less visible. 

The SI2 diamonds, on the other hand, have more noticeable inclusions that make their clarity lower. In other words, they have inclusions that are visible to the naked eye.

However, if you search hard, it is possible to find even an SI2 diamond with barely noticeable inclusions. You can ask your jeweler to try and find you one of these if you only have the budget for an SI2 diamond. 


How to Inspect

Another thing to notice when buying SI2 diamonds is to look at them from different directions, especially the top and edges, because only then will you be able to see any inclusions.


There is also a difference in the price value of the two. 

A 1-carat SI1 diamond is sold for around $4,000 and can reach as high as $8,000 to $10,000. However, the price can go up and down depending on the stone’s carat weight, cut, and color.

An SI2 diamond starts around $2,500 and can go up to $7,000 or more, depending on the quality. You can see that there is a considerable difference even within the price value of the SI range of diamonds. 

Which Is Better: VS Diamonds or SI Diamonds

Even though it is an individual choice to buy the diamonds you like the most, VS diamonds are better than SI diamonds on the clarity chart!

Most people who want to buy a diamond for their loved one care about clarity, which is why VS diamonds are more in demand than SI diamonds. 

  • Firstly, VS diamonds are cleaner in comparison to SI diamonds. 
  • Secondly, they have fewer flaws than the SI range of diamonds

Because of these reasons, people may want to choose VS diamonds over SI. On the other hand, a VS diamond is usually priced higher than SI diamonds due to better clarity and fewer flaws.

Despite the comparison between the two, you would not be able to notice the imperfections in either of them with your bare eyes. You can only see them with a 10x magnification lens. So, you can choose either depending on your budget. 

Which diamond you choose also depends on factors like design, price, and carat weight. So by all means, choose the one you want to buy if clarity alone is not your priority. 

How Much is a 1 Carat SI Diamond Worth?

Price is subject to many factors, including the shape of the diamond as well as the color. It also depends on where you are buying the diamond from – online or through retail. A high-quality 1-carat SI diamond in a round brilliant cut can cost you up to $5,000.

The more popular the cut, design, or size of the SI diamond, the higher its price will be. On average, a typical sized SI1 diamond for 1 carat would start from $3,000 and can go up to $5,000 or perhaps more. 

An SI2 diamond, due to lower clarity and more visible inclusions, starts somewhere close to the $2,500 price range and can go up to $4,000, depending on factors like size and design. 

The below list of sizes and cuts of SI diamonds might help you get an idea. 

  • A round brilliant cut 1ct SI1 diamond can cost around $4,200 – $4,500. 
  • A princess-cut 1ct SI1 diamond will retail for about $4,600 to $5,000.
  • The Royal-Asscher cut for a 1ct SI1 diamond would probably cost you around $3,300 to $3,500. 
  • Odd shapes such as pear cuts would probably cost between $3,500 to $3,800. Pear-shaped diamonds look like teardrops and are more often used for earrings than finger rings.
  • A radiant cut 1ct SI1 diamond would go for about $3,000 – $3,400.

As you can see, there is a broad range in which these diamonds sell, depending on the shape you would like to buy. But one thing is for sure – these are much more reasonably priced than F or VS grade diamonds, which can be exorbitantly expensive but look almost the same to the naked eye.

When Should I Buy an SI Diamond?

SI diamonds are perfect for those who want to own clean-looking diamonds but do not want to pay an unusually high price. 

However, there are still three important things you should consider when buying a diamond. We have discussed these below.


SI diamonds are perfect for those on a budget looking for something nearly flawless yet elegant. They have a lower price than VS (Very Slightly Included) diamonds, but their inclusions cannot be noticed or caught by a naked eye. 

A typical 1ct VS2 diamond might cost you about $1,500 – $2,000 more than a typical 1ct. SI2 diamond. After all, why should you pay for something that you can get at a much lower price and without anybody knowing about it? 

Buying Style 

If your buying style includes looking around for a handful of products (or more) before finalizing the best item that suits your needs, you can opt for the SI diamond range. 

I would recommend SI diamonds for people who like to shop around because you will have to get into the details of the diamond. For example, you need to ensure that the diamonds don’t have flaws or imperfections easily visible to the naked eye. 

If you are looking to buy a diamond with perfection no matter the price, then an SI diamond might not be the choice for you. However, suppose you are the person who knows about the characteristics of the SI diamond range and doesn’t mind the inclusions as long as they are invisible to the eye and come at a low price. In that case, SI diamonds could certainly be for you. 

Diamond Shape 

If you are looking for an elegant yet sparkly diamond with a brilliant cut, the SI diamond range is for you! It is usually available in round and princess shapes and thus, is the best bet for those who want to buy an ethereal piece on a budget. 

The emerald cut shows flaws quite visibly, as do the Asscher-cut diamonds. SI diamonds, however, are designed to hide imperfections from inexperienced eyes and are thus the perfect choice for those looking for a round or princess-cut design. 

Frequently Asked Questions About SI Diamonds

Is SI diamond clarity good?

SI diamonds can look flawless to most people. Their flaws are only visible to an expert with a magnifying glass. Thus, it is safe to say that diamond clarity SI is an excellent choice for those who are looking to buy a high-quality diamond within a budget. 

Are SI diamonds worth buying?

SI diamonds are worth buying and have a great purchase value! They have inclusions, but only experienced individuals can catch them. 

Most people who aren’t too driven by flawless perfection tend to buy SI diamonds, for they come at a lower price and can look no less imperfect than other clarity diamonds.


Wrapping Up

I hope this article helped you understand SI diamonds and how they can make for a great choice for anyone looking to buy a diamond on a budget. 

All said and done, the diamond that you buy has to be a perfect match with your expectations, your budget, and your heart’s desires.

SI diamonds suit a certain set of people, but may not be for everyone. Thank you for reading, and do give SI diamonds a look if you are in the market to buy a diamond.

Related article:
How To Buy The Best Diamond For Money?
Lab-Created Salt and Pepper Diamonds


James Allen Logo

James Allen is our most recommended online jeweler that guarantees a wonderful online shopping experience. You will find the most beautiful and best quality diamonds available for very competitive prices.

James Allen Diamond Rings