Diamond Education
Diamond Clarity
Graded under 10x magnification, but bought with the naked eye. Understanding the gap between those two things is where the money is.
By 25karats · Updated 2026 · 6 minute read
Clarity measures a diamond’s internal inclusions and surface blemishes: the marks left by the conditions it grew in. Almost every natural diamond has them. Genuinely flawless stones are so rare that most jewelers will never handle one.
Here is the thing the grade does not tell you: clarity is assessed under 10x magnification, but nobody wears a diamond under a loupe. What matters is whether you can see anything without one.
The clarity scale
| Grade | Meaning | Visible to the eye? |
|---|---|---|
| FL / IF | Flawless / Internally Flawless | No, and extremely rare |
| VVS1 / VVS2 | Very, very slightly included | No, hard for a grader to find at 10x |
| VS1 / VS2 | Very slightly included | No: the value sweet spot |
| SI1 / SI2 | Slightly included | Sometimes, SI1 is often eye-clean, SI2 less reliably |
| I1 / I2 / I3 | Included | Yes, and may affect brilliance or durability |
IF: Internally Flawless
VVS: Very, Very Slightly Included
VS: Very Slightly Included
SI: Slightly Included
Buy eye-clean, not flawless
“Eye-clean” means no inclusion is visible to normal vision at a normal viewing distance. It is not a graded term, which is exactly why it is useful: it describes what you will actually experience.
The catch is that clarity grades describe severity, not visibility. Two SI1 diamonds can look completely different depending on where their inclusions sit, which is why an SI stone should always be viewed, or at least inspected on the report’s plot, before buying.
What determines the grade
Graders weigh five things, and only one of them is how many inclusions there are.
Position: the one that matters most
An inclusion directly under the table sits in your line of sight and can reflect around the stone. The same inclusion near the girdle, where a prong will cover it, is far less consequential. Check the plot on the report to see where they sit.
Size
A single larger inclusion drops the grade further than several tiny ones.
Number
More inclusions generally means a lower grade, though a scattering of pinpoints matters far less than one well-placed feather.
Nature
What kind it is. A feather that reaches the surface is a potential durability problem; a crystal fully enclosed in the stone is not. See our guide to inclusions and blemishes.
Relief
How sharply the inclusion contrasts with the surrounding diamond. A dark crystal stands out; a transparent one of similar refractive index may barely register.
Shape and size change what you need
Clarity is not a single target. Two things move it:
- Step cuts show everything. Emerald and asscher cuts have large, open, mirror-like facets with nowhere for an inclusion to hide. Buy VS2 or better in those shapes.
- Brilliant cuts hide a lot. Round, cushion, radiant, and princess scatter light in every direction, which conceals small inclusions well. SI1 is frequently eye-clean here.
- Bigger stones need better grades. A larger table is a larger window. An SI1 that is eye-clean at half a carat may not be at two carats.
See our diamond shapes guide for how each shape behaves.
Clarity in lab-grown diamonds
Lab-grown diamonds have inclusions too, they grow as crystals and pick up their own characteristics, though the types differ from natural ones. IGI grades them on the same FL-to-I3 scale. The practical difference is price: because lab-grown runs roughly 40–60% below natural for comparable specs, a VS1 or VVS2 costs far less than it would in a mined stone, so there is little reason to settle for an SI you have not seen. See our lab-grown diamond guide, or filter our inventory by clarity.
See it on real stones
Browse IGI-certified lab-grown diamonds by shape, carat, color, clarity and cut, at roughly 40–60% less than comparable natural stones.
More on diamonds: The 4Cs, Cut, Color, Carat weight, Shapes, Inclusions, Certificates, and Conflict-free.