Facet Rough Clarity Grades: VVS, VS, SI, Eye Clean and Loupe Clean Explained

Most gem cutters have run into this: a nice piece of rough online, and the listing is full of letters half-remembered from a gem show. VVS. VS. SI. Eye clean. You know they matter, but almost no supplier explains what they actually mean before you pay.

Clarity grades describe what is hiding inside an uncut stone: the type, size, and position of its inclusions, which is what decides how much usable gem you actually cut out of it. The cleaner the rough, the higher the price, and usually the more finished stone you recover.

What is clarity in facet rough gemstones?

Clarity in facet rough is a measure of the internal and surface features, inclusions and blemishes, that determine how much usable gem a cutter can recover from the stone.

It covers the presence, type, size, and position of inclusions (features inside the stone) and blemishes (features on the surface). Cut, polished stones get graded against standardized lab systems. Facet rough does not work that way. Grading here is practical, built on trade experience rather than a certificate, but it matters just as much.

Rough gemstones can carry several kinds of inclusions:

• Needles: thin, elongated mineral crystals running through the stone

• Feathers: small fractures or cleavage planes that look like the barbs of a feather

• Clouds: clusters of microscopic inclusions that create a hazy patch

• Crystals: mineral crystals from a different species trapped inside the host stone

• Growth tubes: hollow channels left over from crystal growth

• Colour zoning: uneven colour distribution, common in sapphire and tourmaline

When a dealer lists a piece of faceting rough as VVS, VS, SI, or eye clean, they are telling you how much of that rough is affected by these features, and how much extra work the cutting will take because of them.

Why clarity grading matters more for rough than cut stones

Clarity matters more in rough material than in a finished stone because a cutter can hide problems in a polished gem through orientation, while rough forces you to buy that decision before it has been made.

When you look at a faceted gem, the cutter has already made every choice for you. They oriented the stone to hide inclusions, kept feathers away from the table facet, and used the girdle angle to bury problem zones. What you see is the best result that piece of rough could give.

When you buy rough, you are buying potential, not a finished result. A heavily included stone limits your orientation options. You might cut a smaller stone to dodge a feather, or accept a small window where a cloud sits. Either way, your yield drops, and yield is simply the weight of finished stone you get back from the rough you paid for.

A real example: a 10-carat piece of VS-grade tourmaline rough might yield one clean 4.5-carat faceted stone. The same 10 carats in SI grade, with a feather running through the middle, might give you two smaller stones of 1.8 and 2.2 carats, or it could fracture during cutting and give you nothing at all. Same starting weight, very different outcome.

Knowing your clarity grade before you buy is one of the simplest ways to protect what you spend on rough.

VVS: Very Very Slightly Included

VVS is the highest clarity grade found in commercial facet rough: inclusions are hard to find even under 10x loupe magnification, and invisible to the naked eye.

Best for: precious stones like sapphire, ruby, and emerald, collector-grade pieces, and cutting where you want maximum yield.

What VVS rough usually looks like:

• Inclusions are pinpoint-sized, or extremely fine needles confined to a small area

• No feathers, fractures, or cleavage planes of any real size

• Colour is even, or shows only minor zoning well away from where the table facet would sit

• The stone reads as transparent, with no haze or cloudiness

• Under 10x magnification, you have to go looking for the inclusions to find them

VVS rough is what you reach for when cutting fine aquamarine, premium garnet, or any stone where you need real flexibility in how you orient it. Because the cutter can place the table facet almost anywhere, VVS gives the best yield ratio of any grade you will buy regularly.

Who should buy VVS: experienced cutters making finished gems for jewellery, dealers building fine inventory, and anyone working with precious stones like emerald, sapphire, or ruby, where the finished stone's value justifies paying more for the rough.

VS: Very Slightly Included

VS is the grade most working gem cutters actually buy, sitting at the best balance of quality and price: inclusions are minor and visible under 10x magnification, but the stone can usually still be oriented to produce a clean finished gem.

Best for: semi-precious stones, intermediate cutters, and a good yield without paying VVS prices.

What VS rough usually looks like:

• Inclusions show up under a 10x loupe but stay small and few

• May have fine needles, small crystals, or minor feathers, but not through the zone you would actually cut

• No large fractures or cleavage planes that put the cut at risk

• Eye clean, or very close to it, when you hold it at arm's length in good light

• Gives you real orientation choices; the cutter can usually work around the inclusions

VS material works well for apatite, amethyst, citrine, and most semi-precious stones. When a dealer says “good quality” rough without giving you a grade, this is usually what they mean.

Who should buy VS: most cutters, most of the time. VS is the sweet spot, clean results in the majority of cases without paying the VVS premium.

SI: Slightly Included

SI rough has inclusions you will notice under 10x magnification, and depending on where they sit, you may see them with the naked eye too. This grade takes the most skill to cut well, but it also costs a lot less per carat.

Best for: practice material, cabochon candidates, large tumbled projects, and species that are naturally heavily fractured.

What SI rough usually looks like:

• Inclusions are clearly visible under a loupe with barely any searching

• May include noticeable feathers, clouds, colour banding, or trapped crystals

• Orientation options are tight; you have to plan carefully around the inclusions

• Some SI material can still come out eye clean in the final cut if oriented well

• Higher risk of fracture during cutting if a feather sits near the girdle

• Lower yield overall; expect a smaller finished stone relative to the rough weight

SI is not automatically bad rough. Emeralds, for instance, are naturally included as a species, so SI can be a perfectly normal quality for emerald. It also works well for beginners still building their cutting skills, or for lapidary work where you are cutting cabochons instead of faceted stones. Our lapidary rough collection is a good place to look for SI and cabochon-grade material.

Who should buy SI: beginners learning to facet, cutters working with naturally included species such as emerald or certain tourmaline origins, and anyone who needs budget material for practice or cabochons.

Eye clean: what this term actually means

Eye clean rough has inclusions you cannot see without magnification; they disappear when you look at the stone with the naked eye from a normal viewing distance of roughly 25 to 30 centimetres.

Best for: buyers who want a clean-looking finished gem without paying loupe-clean prices.

Worth noting: eye-clean rough can still show inclusions under a loupe. What matters is that those inclusions will not show up in the finished, faceted stone once it is worn or displayed. And eye clean describes the rough as it will likely cut, not a guarantee; if the cutter orients the stone poorly, a marginal inclusion can still end up right under the table facet. Skill still matters here.

Eye-clean rough usually falls somewhere between VS and lower VVS. Many dealers use the term interchangeably with VS, though technically eye clean is about visibility rather than the size or count of inclusions. You will see it listed on stones like chrome diopside, aquamarine, and apatite rough.

Who should look for eye clean: anyone cutting for jewellery, where what the finished stone looks like matters more than what a loupe would find.

Loupe clean: the top tier

Loupe clean sits at the very top of facet rough clarity grading: no inclusions are visible even under 10x magnification, and the material looks completely flawless at standard gemological examination power.

What loupe-clean rough usually looks like:

• Zero inclusions visible at 10x under good lighting

• Fully transparent and internally clear throughout

• Full orientation freedom; the cutter can place the stone however they like

• The highest yield ratio of any grade, with nearly all the rough weight converting to finished gem weight

• The highest price per carat of any clarity grade

Loupe-clean rough is rare for a lot of gemstone species. For stones like alexandrite, fine ruby, or Colombian emerald, truly loupe-clean rough is genuinely scarce and priced accordingly. For species like amethyst or citrine, loupe-clean rough is far easier to find and much more affordable.

Who should buy loupe clean: advanced cutters working on collector pieces, jewellers setting precious stones into high-value pieces, and anyone whose goal is the highest possible clarity grade in the finished gem.

Quick comparison: clarity grades at a glance

Which clarity grade to buy for each gemstone type

Not every gemstone species gets graded against the same yardstick. A gemologist looks at ruby very differently than amethyst. Here is how clarity expectations shift across the species faceters buy most.

Naturally included species: lower grades are normal

Some gemstones grow with heavy inclusions built into their crystal structure. For these species, SI, or even more heavily included material, can be genuinely good rough:

• Emerald: known for its “jardin,” or garden of inclusions. VS counts as excellent here. Eye-clean emerald rough is rare, and priced like it.

• Ruby: fine ruby above VS clarity is hard to find. SI ruby still cuts beautiful stones.

• Alexandrite: natural alexandrite is almost always included. Eye-clean alexandrite rough commands very high prices.

Typically clean species: aim for VS or better

These species tend to form with fewer inclusions, so buyers expect higher clarity as standard:

• Aquamarine: usually eye clean or better. SI aquamarine reads as low quality.

• Amethyst and citrine: quartz-family stones often come in at VVS or loupe clean. Do not settle for SI amethyst unless you are buying it specifically for practice.

• Apatite: fine faceting apatite should be VS or eye clean at minimum.

• Garnet: depends heavily on the species. Spessartine tends to run clean, while demantoid typically shows the characteristic horsetail inclusion and is still prized despite it.

• Chrome diopside: aim for eye clean or VS. The dark body colour in this stone can hide inclusions that would otherwise be obvious.

Variable species: check before you buy

• Tourmaline: varies a lot by origin and colour. Some Afghan material runs clean; Brazilian Paraíba can be heavily included. Read the clarity description carefully.

• Sapphire: blue sapphire from Ceylon and Kashmir tends to run cleaner than material from Thailand or Australia. VS is the standard expectation for fine sapphire.

How clarity grades affect price per carat

Clarity grade is one of the biggest drivers of facet rough price per carat, and the relationship is not a straight line. It gets steep near the top, especially for precious stones. As a rough guide for commercially available wholesale facet rough:

Those multipliers apply within a species, at the same size and colour. A loupe-clean emerald does not just cost ten times as much as an SI emerald of the same size; it can run 100 times more, because eye-clean emerald rough is scarce to begin with.

For most semi-precious rough, VS or eye-clean grade gets you 80 to 90 percent of the result of VVS for 40 to 50 percent of the price. The extra cost of that last clarity step rarely pays for itself unless you are cutting fine stones for a professional jewellery market.

How to check clarity in facet rough yourself before buying

You can check clarity in facet rough with a 10x loupe, a directional light, and a four-position lighting check that reveals inclusions surface photos miss.

Tools you need

• A 10x loupe: the standard gemological magnification. A decent triplet loupe is worth the money.

• A strong directional light: a fibre optic or LED penlight. Hold it against the side of the stone (oblique lighting) to catch inclusions that light passing straight through would miss.

• A diffused overhead light: for checking colour zoning and cloudiness.

The four-position check

Work through these positions in order:

1. Transmitted light (backlit): hold the stone in front of a light source. This shows overall transparency and any large fractures or colour zones.

2. Oblique, side-lit: light enters from the side. This is the best way to catch fine needles, feathers, and growth tubes that backlighting misses.

3. Reflected light (dark field): hold the stone against a dark background with light coming over your shoulder. This is where surface blemishes and near-surface inclusions show up most clearly.

4. Naked eye at arm's length: your final check. Set the loupe down and just look. Is it eye clean?

Buying facet rough online

Clarity claims matter a lot more when you cannot hold the stone yourself. At Gemstone Insider we describe clarity honestly on every listing, and here is what you should expect from any supplier:

• Multiple photos from different angles, including backlit shots

• Close-up macro shots of the interior

• A specific clarity grade, VVS, VS, SI, or eye clean, rather than a vague phrase like “nice quality”

• Video or loupe footage where available

• A clear returns policy if the stone does not match its description

Every listing in our faceting rough collection carries an honest clarity description. You can also browse our full range of rough gemstones, including rough crystals and wholesale rough lots.

Frequently asked questions

What does VVS mean in facet rough gemstones?

VVS stands for Very Very Slightly Included. In facet rough, it means the inclusions are hard to find even under 10x loupe magnification and invisible to the naked eye. VVS rough gives the cutter the most freedom in orientation and the best possible yield, which is why it is the top clarity choice for fine gemstones.

What is the difference between eye clean and loupe clean rough gemstones?

Eye clean means you cannot see the inclusions without magnification; the stone looks clean at normal viewing distance. Loupe clean is a step above that: no inclusions show up even under 10x magnification. Both grades produce a visually flawless finished gem, but loupe-clean rough is rarer and costs a lot more.

Is SI clarity facet rough worth buying?

Yes, for the right job. SI rough is a solid choice for beginner cutters who need affordable practice material, for naturally included species like emerald where SI is a normal range, and for cabochon cutting rather than faceting. Skip it for precious stones headed for jewellery, since yield will be lower and inclusions may still show in the finished piece.

Which clarity grade gives the best value for money?

For most faceters, VS or eye-clean grade is the best value. Both produce clean finished stones in most cases, without the VVS or loupe-clean price tag. For semi-precious stones like aquamarine, apatite, tourmaline, and garnet, VS rough gives strong cutting results at a price that still makes sense.

How does clarity grade affect yield when cutting facet rough?

Clarity has a direct effect on yield, the share of rough weight that ends up as usable finished stone. Loupe clean and VVS rough can yield 75 to 95 percent of the rough weight. VS typically runs 60 to 75 percent. SI can drop as low as 40 to 60 percent, and if a feather or fracture causes the stone to break during cutting, the loss can go higher still. That is why it pays to think through yield before you buy.

Do all gemstone species use the same clarity standards?

No. Expectations shift by species. For naturally included gems like emerald, ruby, and alexandrite, SI or VS counts as very good. For species that typically form clean, like aquamarine, amethyst, and citrine, buyers expect VS or eye clean as a baseline. Judge clarity against what is normal for that species. An SI emerald can be a better stone than an SI aquamarine, simply because clean aquamarine is much easier to find.

How can I check the clarity of facet rough before buying online?

Look for listings with multiple photos from different angles, especially backlit and side-lit shots, close-up macro photos of the interior, a specific clarity grade rather than a vague description, and video or loupe footage where it is available. If a listing is missing these, ask the seller for more photos before you buy. Gemstone Insider grades every facet rough listing honestly for exactly this reason.

What tools do I need to check clarity in facet rough?

A 10x triplet loupe is the main one, the standard tool gemologists use worldwide. A strong directional LED or fibre optic light matters too; holding it against the side of the stone reveals inclusions that regular light misses. Finish with a naked-eye check at arm's length to see if the rough reads as eye clean.

What is the best clarity grade for beginner gem cutters?

Start with SI or lower VS rough in inexpensive species like quartz (amethyst, citrine) or apatite. That keeps costs down while you are still breaking stones and misjudging orientation, which happens to everyone early on. As your skills improve, move up to VS and then VVS in more valuable species, and let your confidence build before you invest in premium material.