Visual chart
Diamond Clarity Chart
GIA clarity grades from Flawless to Included. The most important real-world threshold is between SI1 (often invisible to the eye) and SI2 (often visible). Spending past VS2 buys you inclusions even loupes can't see.
| Grade | Meaning | Eye visible? |
|---|---|---|
FL Flawless | No internal or external flaws under 10× magnification. | No |
IF Internally Flawless | No internal flaws; minor surface marks under 10×. | No |
VVS1 Very Very Slightly Included 1 | Inclusions extremely difficult to see under 10×. | No |
VVS2 Very Very Slightly Included 2 | Inclusions very difficult to see under 10×. | No |
VS1 Very Slightly Included 1 | Inclusions difficult to see under 10×. | No |
VS2 Very Slightly Included 2 | Inclusions somewhat easy to see under 10×. | No |
SI1 Slightly Included 1 | Inclusions noticeable under 10×, sometimes eye-clean. | Maybe |
SI2 Slightly Included 2 | Inclusions easy to see under 10×, often eye-visible. | Often |
I1 Included 1 | Inclusions obvious to the naked eye. | Yes |
I2 Included 2 | Inclusions affect transparency. | Yes |
I3 Included 3 | Inclusions affect transparency and brilliance. | Yes |
Buy rule: "Eye-clean SI1" is the price-performance sweet spot. VS2 is the ceiling at which clarity stops mattering visually. Above VS2 you're paying for spec, not appearance.
What a clarity grade actually measures
Clarity counts two things: inclusions, which sit inside the stone, and blemishes, which sit on its surface. A grader looks face-down at 10× magnification under controlled light and records what is there, how big it is, how many there are, where they sit, and how much contrast they have against the stone. The grade comes from all of those together rather than from a headcount — one dark feather under the table can matter more than a scatter of pinpoints near the girdle.
The vocabulary on a report is short and specific. A crystal is a mineral trapped inside while the diamond grew. A feather is a small internal fracture. A cloud is a tight cluster of pinpoints that reads as a hazy patch. A needle is a long thin crystal, aknot is a crystal reaching the surface, and anatural is a piece of the original rough left on the girdle on purpose. Chips, beard and abrasion are handling damage rather than growth features, and they usually say more about the stone's history than about its quality.
Position decides visibility. Anything directly under the table — the flat face you look through — is out in the open. The same inclusion near the girdle can vanish behind a prong, and a pale inclusion larger than a dark one can be harder to spot because it blends into the reflections. Two stones graded identically can therefore look completely different, which is why the plot diagram on a report tells you as much as the letter grade does.
Where the value actually sits
Eye-clean SI1 is the usual answer for a round brilliant around one carat: real inclusions under a loupe, nothing visible to an unaided eye, and a meaningful discount against VS2. Move up to VS2 for a stone approaching two carats, for one with a dark inclusion sitting centrally, or for a step cut.
Step cuts — emerald, Asscher and their rectangular cousins — behave differently. Their broad flat facets act like a window instead of a mirror, so nothing is hidden: colour shows earlier, clarity shows earlier, and buyers of these shapes commonly want VS or better instead of the SI1 they would accept in a round. Brilliant-cut shapes do the opposite, scattering light across the crown until small inclusions disappear into the pattern.
At the top of the scale, FL and IF buy a distinction that cannot be seen without magnification. Nothing about a Flawless stone returns more light or looks more alive than a VVS2 of the same cut, so that premium is paid for the specification. Above VS2 most of the retail gap is documentation rather than appearance, and someone who plans to wear the ring is usually better off stepping one grade down and moving the difference into cut or carat.
Grading is a trained judgement, not a machine reading. The same stone submitted twice can come back a grade apart, and two labs can disagree on the same stone — one reason identical grades sell across a range instead of at a single number. The report details beyond the letter, meaning inclusion type, colour, position and any fluorescence note, are what separate a cheap VS1 from an expensive one.
Frequently asked questions
Is SI1 always eye-clean?
For a round brilliant under about one and a half carats, usually yes — but it depends on the inclusion. A pale cloud near the girdle is far easier to live with than a black crystal directly under the table, and larger stones or step cuts show the same grade more readily. The plot tells you more than the letter.
Does a higher clarity grade make the diamond sparkle more?
No. Sparkle comes from cut, meaning how well the facets return light. Clarity only enters the picture when an inclusion is big or dark enough to interrupt that light path or to be seen without a loupe, which happens well below the top of the scale.
Do different labs grade clarity differently?
Yes. GIA is the reference the trade calibrates against and some labs are a grade more generous on the same stone. That gap is priced: a GIA VS1 and a house-certified VS1 do not sell for the same amount, and a stone with no report at all is discounted further because the buyer carries the grading risk.
Can an inclusion be removed?
Sometimes — laser treatment can fade a dark inclusion and re-polishing can clear a surface blemish — but both cost weight and any treatment must be disclosed. For a stone being sold, original condition is worth more than a small grade improvement, because the buyer prices the discount first.