Of the four C’s, clarity probably makes the least impact on your diamond. Most imperfections on a diamond are microscopic and not possible to see with the naked eye. Only under a 10x magnification are these flaws visible.
Of course, there are diamonds with larger flaws, but most reputable jewellers will not sell diamonds with visible imperfections or fractures that threaten the integrity of the diamond.
What is Clarity?
Clarity is the number of imperfections, that is, flaws, scratches, cracks, blemishes and inclusions, in a diamond. Clarity also measures the size of all the imperfections in a diamond. Because diamonds are formed deep in the earth, under tons of pressure and extreme heat, it is very common for them to have blemishes either internally or externally, or both. However, most of the blemishes are not discernible and do not affect the overall beauty of the diamond. Very rarely, a diamond will be found with no inclusions. It is classified as a flawless diamond and is incredibly expensive because of how rare it is.
The Clarity Scale
Gemologists measure and assess each diamond and grade it according to a scale. The scale measuring clarity begins at Flawless and ends at I3. The price of the diamonds typically follows the scale. Very rare, flawless diamonds are costly, while lower graded diamonds cost less.
• Flawless (F) – Absolutely no flaws or blemishes, internally or externally.
• Internally Flawless (IF) – No internal imperfections.
• Very, Very Slightly Included (VVS1, VVS2) – Even under 10x magnification, it is still difficult to discern flaws.
• Very Slightly Included (VS1, VS2) – Flaws and imperfections not visible to the naked eye.
• Slightly Included (SI1, SI2) – Blemishes clearly visible under magnification, and can be visible to the naked eye.
• Included (I1, I2, I3) – Clear blemishes and inclusions. These inclusions can affect sparkle and light-reflection. Many reputable jewellers do not sell diamonds of this grade, although they cost much less than the other grades.
What Clarity is Right for You?
Many buyers choose to buy diamonds with a Slightly Included grade or higher. The most popular is the SI1, because even if it is flawed, no one is going to be looking at your ring under a microscope, which is the only way they can see the imperfections. Once the diamond is in its setting, it is practically impossible to notice any inclusions at all, and an SI grading still has all the sparkle and brilliance of a flawless diamond.
If you are on a tight budget, buying an Included diamond (I1, I2, or I3) can be an excellent idea, because many of the blemishes will be hidden in the setting of the ring or under the prongs.
One thing to keep in mind is that the shape of your diamond also has an impact on how clarity affects the overall brilliance. Because of the different ways the facets are cut depending on the shape, some flaws can be more visible. For example, a round brilliant cut will show fewer inclusions than an emerald cut, simply because of the way the facets are cut to maximize light reflection.
Larger diamonds have larger facets, which means that blemishes can be more visible than they are on smaller diamonds.