What is the difference between VS and SI Diamond Clarity

What is the difference between VS and SI Diamond Clarity

Posted by Sharif Khan on 3rd Aug 2022

Bottom Line

  • GIA-graded VS1 and VS2 diamonds have very high clarity grades. They should always be considered eye-clean to the naked eye.
  • The larger the diamond, the more visible the inclusions. Therefore, VS2 diamonds above the 2.5-carat range should be carefully inspected.
  • SI1 should be considered eye-clean in the 1-carat range. It can be eye-clean in the 2-carat range, depending on the location and type of inclusions. Follow our diamond clarity guide carefully for a thorough examination.
  • SI2 is a decent clarity grade in the 1-carat range but should not be expected to be eye-clean in diamonds weighing more than 1.5 carats. You might find 95-99% eye-clean SI2 diamonds in the 1-carat range if you are lucky.
  • While VS1/VS2 are suitable investment grade ranges, SI1/SI2 are great budget options.
  • Use Jame Allen's Ultra HD 3D Technology to assess the location and size/color of inclusions before purchasing to make an informed decision. We emphasize avoiding large black crystals in the center of the diamond. Also, please avoid SI1/SI2 diamonds, whose clarity grade is based on clouds (look at the comments section of the GIA report, and if it states "clarity grade based on clouds," avoid that diamond as it will look dull). 

GIA Diamond Clarity Scale

Diamond Clarity – Overview

The clarity of a diamond refers to how clean a diamond is. Almost all mined and lab-grown diamonds have inclusions of some type. These inclusions are imperfections that work to create uniqueness in each diamond. A prominent inclusion causes a diamond to have a lower clarity rating, which could affect its value and quality.

The inclusions in a diamond could be several things, such as crystals, clouds, trace minerals, or feathers. They are usually tiny but can be quite noticeable in an obvious position.

When purchasing a diamond, the higher clarity, or flawless diamonds, are the most valuable and will have a much higher price. Conversely, the lower you go on the clarity scale, the less you will pay for a diamond. Therefore, if you are sticking to a budget, choosing a lower clarity diamond would make sense. However, please keep in mind that if inclusion or blemish is too pronounced, it could negatively affect the brilliance or sparkle of a diamond.

The Diamond Clarity Grade

All loose diamonds are graded on a clarity scale that considers the size, number, and type of inclusions. This scale was created by the Gemological Institute of America (GIA). There are six categories in the grading scale and eleven diamond clarity grades. The scale ranges from FL and IF, Flawless or Internally Flawless, to I, Included. FL and IF diamonds have no visible inclusions or imperfections when viewed under 10x magnification. I diamonds have inclusions that are easily viewed with the naked eye.

Finding a balance between these two grades will help you fit the diamond you want into your budget. It will also allow you to buy a visually appealing diamond that still has a wonderful sparkle.

VS vs. SI diamonds

Choosing a diamond graded as SI or VS is an excellent idea to make the most of your diamond budget. These grades are clean to the naked eye and have almost no visible difference.

VS diamonds can be graded as VS1 or VS2. These diamonds are Very Slightly included and have inclusions that can be viewed with a 10x magnification. These fall third on the grading scale and are regarded as good quality diamonds; you should not notice any blemishes or inclusions when they are set.

SI diamonds can either be graded as SI1 or SI2. They are rated fourth on the diamond clarity scale and are Slightly Included. These inclusions can easily be seen using 10x magnification but most often cannot be noticed with the naked eye through the crown of the diamond. However, in some cases, depending on where the inclusion is based, it might be slightly noticeable to the naked eye. These are fair-quality diamonds to purchase and can save a great deal when fitting a diamond into your budget.

It is usually recommended not to go below a VS diamond. But if you find an eye-clean SI diamond, you can gain maximum value from purchasing it. An SI1 diamond that is visibly clear to the eye will seem almost identical to a VS diamond but will be a cheaper option. Hence, it is a good idea to buy an SI1 diamond, which is clear to the eye.

Searching for an SI1 diamond that you are happy with will be worth your while. However, not all SI diamonds are visibly similar; some will have a haziness that is apparent with magnification, while others may have a slight haziness that can be seen with the naked eye. Compare diamonds together to make the right choice!

James Allen

Clarity Grading Factors

Five different factors can affect the clarity of the diamond. These factors are size, nature, number, relief, and location.

Size: The larger the inclusion in a diamond, the lower the clarity grade will be. A large inclusion can also impact the durability of the stone, which is why a lower-grade diamond should not be bought.

Nature: Nature refers to the type and depth of an inclusion. Inclusions penetrate deep within a diamond, whereas blemishes are only confined to the stone's surface.

Number: The number of inclusions is important; the larger the number of inclusions or blemishes, the lower the clarity grade will be. However, if the inclusions are not visible, it will not impact the overall number rating.

Location: It refers to the position of the inclusion or blemish in a diamond. The closer the inclusion is to the center of the table, the more effective it will be on clarity. This is because it interferes with the way light reflects within the diamond. Inclusions closer to the girdle are challenging to see, but they could damage the stone if they are close to the surface.

Relief: Relief is the distinctness of inclusion when viewed within the diamond. Therefore, the greater the relief, the greater the effect on the clarity grade.

The Importance of Clarity

While all 4Cs—clarity, cut, color, and carat—should be considered when buying a diamond, clarity should be one of the main deciding factors. Going below an SI1 diamond runs the risk of you purchasing a diamond with a visible inclusion and bad overall sparkle and brilliance. You may also end up buying a diamond with an inclusion that might affect the durability of the stone.

If you are battling to decide between a VS and an SI diamond, we recommend you go for an SI1 diamond. Finding an eye-clean SI1 diamond will help you save a significant amount on your budget, and you will still be left with a beautiful, sparkling diamond that will look gorgeous in any setting.