SI diamond clarity is a popular grade among buyers. Oftentimes, you will also see a diamond whose clarity is labeled as “SI2.” What does this clarity grade mean, and is it a good deal to buy such diamonds?
What Is SI clarity?
Diamond clarity is graded on the basis of how many inclusions and flaws can be spotted in a diamond, under magnification or with the naked eye. (Read more about how diamond inclusions develop.)
According to the scale introduced by the G.I.A. (Gemological Institute of America), the top clarity grade is Flawless (denoted by FL), followed by Internally Flawless (IF), Very, Very Slightly Included (VVS), and Very Slightly Included (VS).
SI (standing for “Slightly Included”) is the next grade, the fifth highest, after which there is only one more grade: Included (denoted by the letter I). (Read our article on I1 clarity.)
SI clarity is the grade assigned to diamonds with inclusions that are easy to see under magnification and may or may not be visible with the naked eye.
What Is SI2 clarity?
The SI clarity grade is further split into two subgrades: SI1 (the higher grade) and SI2.
Click here to see a selection of SI1 diamonds and check out their prices.
SI2 diamonds very often have inclusions that cannot be seen with the naked eye when looking at the stone from above (some inclusions may be visible without magnification if you look really hard for them).
However, if you look at an SI2 diamond from the side, you may be able to see some inclusions.
Click here to see a collection of SI2 diamonds and compare their clarity with that of SI1 stones.
How Is SI2 Clarity Different from SI1 Clarity?
The difference between SI2 and SI1 comes down to the visibility of inclusions.
Whereas flaws in SI1 diamonds can usually be seen only under magnification and are practically invisible to the naked eye, some inclusions in SI2 can be seen without using a loupe or microscope. (For more details on eye-clean diamonds, check out this article.)
The visible flaws in SI2 diamonds will usually be located towards their sides; there should be no big and obvious inclusions located centrally when looking through the top of the stone.
How Is SI2 Better Than I1 Clarity?
I1 clarity is the first subgrade (out of three) of the I-clarity range. When looking at an I1 diamond, you won’t need a loupe to see the stone’s inclusions, even if you view the diamond directly from above. You can see what I1-clarity diamonds look like here.
In contrast, SI2 diamonds’ inclusions are usually not readily visible from the top (although there are some SI2 diamonds whose flaws are more easily seen), and they are generally smaller and less numerous.
It is fair to say that SI2 clarity is the divide between the diamonds with practically invisible inclusions and those with easily noticeable flaws. Read this article on inclusions that you should avoid to learn more about diamond flaws.
Beware of SI2 Clarity Scams
Sometimes, the difference between SI2 and I1 diamonds can be hard to establish for people who are not familiar with the subtleties of diamond clarity definitions.
There are some sellers who may try to exploit this confusion and offer you an I1 stone represented as an SI2 diamond.
However, if you can spot easily visible inclusions when looking at the stone top-down, it may not actually be SI2 (although there are SI2 diamonds that have more visible inclusions).
The best way to prevent scams is to buy only diamonds that are certified. However, it is even more important which lab issued the certificate: Make sure that the issuer is a reputable institution such as the G.I.A. Check out our article on certified diamonds to learn what diamond certification means.
Our advice: To avoid scams, we recommend that you buy diamonds from reputable retailers such as James Allen and Brian Gavin Diamonds, which only sell diamonds certified by labs such as the G.I.A. or A.G.S.
Should You Buy SI2 Clarity?
The main reason SI2 clarity may be a better choice than higher grades is its price: You can save thousands of dollars if you pick SI2 over a diamond graded SI1 or higher.
Another important consideration is what level of clarity you will be satisfied with and how much of a difference it would make if you get a higher clarity stone.
If your diamond is going to be set in a mounting that will cover its sides, an SI2-clarity stone can be a good choice: Its flaws will usually be visible only from the side, which will be concealed by the setting. (Read more about diamond ring settings here.)
However, you should take some time to sort through different SI2 stones in order to find one whose inclusions are less visible because some diamonds of this clarity have flaws that are more visible, even from the top.
In such a case, you can safely go with an SI2 diamond that looks clean from the top, which is the part that will be seen by you and others when the diamond is worn. Just make sure you are comfortable with how visible the stone’s inclusions are before you buy it, and look at a number of different SI2 diamonds to compare them.
You can also check out our guide on how to select a diamond for step-by-step instructions on how to buy the best stone for your budget.
If you are buying an SI2 diamond, make sure that its cut is graded at least Good or higher as its symmetry will determine how much light the diamond will be able to capture. The less light in the diamond, the less brilliance it will exhibit and the more visible any flaws within the stone will be, even when it is looked at from the top.
You should also keep in mind that there are some cuts that have naturally less brilliance than the classic round cut: The emerald cut is such an example (read more about the emerald cut here). In these stones, you may be able to see some inclusions from the top.
Where to Buy Diamonds and Diamond Jewelry?
For diamond jewelry, we highly recommend James Allen because it shows real photos and videos for each diamond so you can take a 360-degree look at any stone before buying it.