What is diamond clarity, and which grade is worth paying for?

What clarity actually measures

Clarity is a grade for how free a diamond is of two things: inclusions, the internal characteristics trapped inside the stone, and blemishes, the marks on its surface. A grader assesses five factors together, the number of characteristics, their size, their type (what they actually are), their position (where they sit, and whether they fall under the table where the eye looks), and their relief (how strongly they stand out against the diamond). It is worth being clear about one thing up front: inclusions are not defects in the everyday sense. They are the marks of how the diamond crystallised deep in the earth over billions of years, and almost every natural diamond carries them. A truly Flawless stone is rare, and most of what separates one clarity grade from the next cannot be seen without a loupe.

The GIA diamond clarity scale, grade by grade

There are eleven grades on the GIA clarity scale, organised into six named categories. Each step down lowers the price for the same cut, colour and carat, often substantially, while the visible difference to the naked eye narrows to nothing for most of the range. This is the full scale, in plain terms:

The clarity grade is one of four. For how it sits alongside cut, colour and carat in a real purchase, see our guide to the 4Cs of diamond grading, and the sibling pages on diamond cut and diamond colour.

Eye-clean: the single most useful idea for a buyer

If you take one thing from this page, take this. A diamond is graded under 10× magnification by a professional, but it is worn in the open, on a hand, across a room. The grade answers a laboratory question; what you actually care about is whether anyone can see an inclusion while you wear it. An eye-clean diamond is one with no inclusions visible to the naked eye at normal viewing distance, about an arm’s length, in ordinary light, even though inclusions are plainly there under the loupe.

Here is why it matters so much to the price you pay. A genuinely eye-clean VS2 or SI1 stone looks identical to a Flawless one once it is set in a ring, because the only difference between them is invisible without magnification. Yet the Flawless stone can cost several times more. Paying up the clarity scale past eye-clean buys a difference that no one, including you, will ever see in normal life. The smart move is to fix an eye-clean target and spend the saving on cut, the one grade the eye genuinely notices, rather than on a clarity grade nobody can see.

The catch, and it is why the grade alone is not enough, is that eye-clean is not a GIA grade and is not guaranteed by the clarity letter. One SI1 can be flawless to the eye; another SI1 of the same grade can show a dark crystal right under the table. The grade tells you the inclusions are similar in size; it does not tell you where they sit. That single fact is the reason a stone must be read on the plot and, ideally, seen, before it is bought.

Inclusion types in plain terms

The GIA plot on a report marks inclusions by type, and the type tells you whether a characteristic is purely cosmetic or worth a second thought. The common ones, in plain language:

• Crystals. A small mineral, sometimes another tiny diamond, trapped inside the stone. Often colourless and invisible; a dark or black crystal under the table is the one that can break eye-clean, because it has high relief and sits where the eye looks.
• Feathers. A small internal fracture, named for its wispy look. Most are harmless and invisible. The only ones that matter for durability are large feathers that reach the surface or sit near a sharp corner or the girdle, where a hard knock could extend them.
• Clouds. A hazy group of microscopic pinpoints clustered together. A small, faint cloud is nothing; a large dense cloud can soften the stone’s brilliance and make it look slightly milky, which is a look problem rather than a durability one.
• Needles and pinpoints. Tiny needle-shaped inclusions or single pin-sized dots. Almost always invisible to the eye and irrelevant to wear; they are simply part of what puts a stone in the VS or SI band rather than VVS.

The short version: most inclusions are about the grade only and change nothing about how the diamond wears. The two to watch are a dark crystal under the table, which is a visibility issue, and a large surface-reaching feather near a vulnerable point, which is the rare durability issue. A working bench reads for both before quoting.

Why clarity is graded at 10×, not by eye

Clarity is assessed under 10× magnification by a trained grader, and the whole grade is defined at that magnification. This matters for value in a way that catches buyers out. A VVS stone and a VS stone can look exactly the same to you across a table, and even an SI1 often does, because the entire scale above eye-clean is describing things you cannot see without a loupe. You are being asked to pay a premium for a laboratory distinction, not a visible one.

Read the other way, this is good news. It means the clarity grade is the easiest place in the 4Cs to save money without losing any visible quality, provided the stone is genuinely eye-clean. It also means the certificate and its plot, not a glance, are how you judge clarity honestly. Our walk-through on how to read a GIA report shows you where the clarity grade and the inclusion plot sit on the document and how to use them, and every stone we sell is GIA-certified so the grade you pay for is independently verifiable.

Where the value sweet-spot is, and where it is not

For most buyers the clarity value sweet-spot sits at VS2 to SI1. At that level a well-chosen, eye-clean stone looks identical to a Flawless one in the hand and costs far less. Below it, SI2 can still be excellent value when the inclusions sit out of the way, but it needs checking because some SI2 stones show. Above it, VVS and IF and FL each cost more for a difference that is invisible once the stone is set; the premium is real, the visual gain is not. Paying up the scale only makes sense if the certificate grade itself matters to you, as a collector specification or for resale, rather than the look.

Clarity does not act alone, either. It interacts with shape and size in ways that change which grade you should target:

So the honest target is not a fixed grade; it is the lowest grade that is genuinely eye-clean for your shape and size. For a round brilliant near a carat that is usually SI1; for an emerald cut it may be VS1. The 4Cs guide sets out how clarity trades against the other three on a real budget, and the diamond prices page shows how each grade moves the figure.

How Prodiam helps you find a genuinely eye-clean stone

The difference between buying clarity well and buying it badly is whether someone reads the stone before you pay for it. As a SADPMR-licensed cutting house and a member of the Diamond Dealers Club of South Africa, that is what we do at Procut DCW in Bedfordview. When you tell us your spec, or simply describe what you want, Darren Etkind pulls the GIA report, reads the inclusion plot, and identifies where the inclusions sit and whether the stone is genuinely eye-clean for its shape and size, not just what its grade implies. We will steer you to an eye-clean SI1 over a VVS2 when the SI1 looks identical and costs far less, because there is no reason to pay for a grade nobody can see.

You see live, fully-landed ZAR prices on the loose diamond search, filter to your grades, and get a firm rand figure for a real, GIA-certified natural stone, referenced to the Rapaport list, that you can verify yourself by report number before committing. Take it loose or set into a custom ring, delivered insured and overnight. Buying from anywhere in South Africa changes nothing, the same plot is read and the same honest grade is quoted. For the most searched size specifically, the 1 carat diamond price in South Africa guide shows which one-carat spec, clarity included, is the best value.

Diamond clarity: common questions

Last reviewed: June 2026.