Best Clarity for Lab-Grown Diamonds: What Grade Should You Buy

Clarity is the most misunderstood of the 4Cs. It is also the grade buyers most often overpay for. The promise of a "flawless" diamond sounds appealing, but the difference between flawless and a stone that looks flawless to the naked eye is invisible to everyone except a gemologist with a microscope. That difference can cost thousands.

This guide walks through the full lab-grown diamond clarity chart, defines what each grade actually looks like in real life, and identifies the clarity range most modern buyers should prioritise. By the end, the decision will feel straightforward rather than technical.

What Diamond Clarity Actually Means

Historically, laboratory-grown diamonds were graded using the same clarity scale applied to mined diamonds, ranging from Flawless (FL) through to Included (I3). Many laboratory-grown diamonds in the market today still carry these traditional clarity grades.

While the Gemological Institute of America (GIA) announced in June 2025 that it would move to a simplified quality assessment system for laboratory-grown diamonds, replacing the traditional D‑Z colour and FL‑I3 clarity grading with two categories, "Premium" or "Standard," the International Gemological Institute (IGI) continues to assess lab-grown diamonds using the traditional 4Cs framework, including detailed colour and clarity grading.

At LOHR, we choose to work exclusively with IGI-certified laboratory-grown diamonds, ensuring a more detailed and transparent assessment of each stone. Beyond certification, every LOHR diamond is further evaluated to our own internal standards for cut, balance, and light performance, guaranteeing exceptional brilliance and refinement.

In practical terms, clarity is less about perfection and more about what the wearer sees at arm's length every single day. Most inclusions are microscopic. Many are invisible even under magnification. The clarity chart exists to standardise what a trained eye sees, not what the average person notices when light catches a diamond on a finger.

At a glance, the chart divides into clear tiers. FL and IF belong to the collector's zone, where rarity drives price more than visible beauty. VVS grades offer invisible perfection: inclusions exist but require a microscope to locate. VS sits as the everyday luxury sweet spot: reliable, beautiful, and priced fairly. SI is the value zone, but one that requires care. I grades, from I1 through I3, are generally avoided in fine jewellery.

How Lab-Grown Diamond Clarity Compares to Natural Diamond Clarity

The grading scale is identical. The distribution of grades, however, differs meaningfully between lab-grown and natural diamonds.

Because growth conditions in a laboratory can be controlled and because lower clarity rough is often diverted to industrial use, a higher proportion of polished lab-grown diamonds fall in the VS-and-above range.

This does not mean lab-grown diamonds are automatically flawless. Inclusions still occur. The types of inclusions differ, which is a useful bridge to the next section. But the average clarity of a lab-grown diamond offered for fine jewellery sits comfortably higher than the average natural diamond.

Inclusion Types in Lab-Grown Diamonds

Every diamond, lab-grown or natural, tells the story of its formation through its inclusions. These microscopic features are not defects in the way a scratch on a lens is a defect. They are natural consequences of crystal growth. In most cases, they are invisible to the naked eye and irrelevant to the beauty of the finished stone.

Common Inclusions Found in All Diamonds

Some inclusion types appear in both lab-grown and natural diamonds. These include:

• Crystals: Small mineral crystals trapped inside the diamond.

• Clouds: A hazy cluster of pinpoints that can appear as a soft blur under magnification.

• Feathers: Small internal fractures that resemble a feather or a fine line.

• Pinpoints: Extremely tiny white or black dots visible only under high magnification.

• Needles: Long, thin crystal inclusions resembling a needle.

• Twinning wisps: A ribbon-like disturbance in the crystal lattice, often associated with twinning planes.

Most of these are microscopic and require significant magnification to see. They do not affect the diamond's performance or durability when graded VS2 or higher.

Inclusions Specific to Lab-Grown Diamonds

The two main growth methods produce subtly different inclusion characteristics.

HPHT-grown diamonds may occasionally contain metallic flux inclusions. These are small remnants of the iron-nickel catalyst used during the high-pressure, high-temperature process. They can appear as tiny dark or reflective specks. In some cases, a strong magnet can attract an HPHT diamond with significant metallic inclusions, though this is rare in gem-quality stones.

CVD-grown diamonds may show graphitic pinpoints, which appear as dark dots of non-diamond carbon or faint growth striations that look like fine parallel lines under magnification.

None of these characteristics makes a lab-grown diamond inferior. They are markers of origin, like a signature. In any stone graded VS or higher, they cannot be seen without magnification.

What "Eye-Clean" Means and Where It Begins

Eye-clean is the single most useful concept for anyone buying a diamond. It is also not an official GIA grade.

An eye-clean diamond is one whose inclusions are not visible to the unaided eye at a normal viewing distance, around 25 to 30 centimetres. That is roughly the distance from someone's hand to their face, or someone sitting next to you at a dinner table. It is the distance at which a diamond is actually worn and admired.

Diamonds graded VS2 and higher are reliably eye-clean across all shapes and sizes. SI1 is often eye-clean, particularly in brilliant cuts such as round, oval, and cushion, where the faceting pattern masks inclusions effectively. SI2 sits in a case-by-case zone, where eye-clean status depends entirely on the location, type, and colour of the inclusion.

For most buyers, eye-clean is the only standard that matters. A diamond that looks flawless from 30 centimetres is, for all practical purposes, flawless.

The Best Clarity for Lab-Grown Diamonds

This is the question that brings most readers here. The answer depends on the shape, the budget, and how much weight a buyer places on a certificate. But a clear hierarchy emerges.

VS1 to VS2 - The Everyday Sweet Spot

For most buyers, VS1 to VS2 is the ideal clarity range. These grades are reliably eye-clean across all shapes and sizes. There is no compromise on light performance. Inclusions, where they exist, require magnification to find. And in the lab-grown market specifically, VS1 and VS2 are abundant, often only modestly more expensive than SI1.

The visual difference between a VS2 and a VVS2 is invisible to the naked eye. The price difference is not. For a diamond that will be worn daily rather than studied under a loupe, VS is the intelligent choice.

VS1 or Higher - For Step Cuts and Larger Stones

Emerald, Asscher, and baguette cuts have long, open facets that act like windows into the stone. They expose inclusions more readily than brilliant cuts. The same principle applies to stones above approximately 2.00 carats, where a larger table and viewing area magnify any imperfection.

For these scenarios, VS1 or higher is recommended. The additional clarity provides a noticeably more refined result, particularly in step cuts where transparency and evenness define the beauty of the stone.

SI1 - The Considered Value Choice

For buyers prioritising carat weight or cut quality, a carefully selected eye-clean SI1 in a brilliant cut can be visually indistinguishable from a VS2. The savings are meaningful.

The key is to review the clarity plot on the grading report and, ideally, request high-resolution imagery before purchase. An SI1 with a small crystal tucked near the girdle is an excellent value. An SI1 with a central cloud or a large feather requires caution.

Grades to Approach with Caution

FL and IF are typically a poor allocation of budget for a stone intended to be worn rather than collected. The visual gain over VVS or VS is imperceptible. The price premium is substantial.

Grades I1 through I3 are generally unsuitable for fine jewellery. Inclusions are obvious to the naked eye. In some cases, surface-reaching feathers can pose durability concerns over a lifetime of wear. These stones are best avoided for engagement rings or daily wear pieces.

How Shape, Setting, and Carat Influence Clarity Choice

Clarity does not exist in isolation. It is chosen in conversation with shape, setting, and size.

Round brilliant: The most forgiving cut. An eye-clean SI1 is often indistinguishable from VS2.
Oval, pear, cushion, radiant, heart: Also forgiving due to brilliant faceting. SI1 works well; VS2 offers peace of mind.
Princess: Moderately forgiving. VS2 is a safe starting point.
Emerald, Asscher, baguette (step cuts): Unforgiving. VS1 minimum, ideally VVS2.
Marquise: Variable. VS2 is recommended.

Setting style also matters. A halo or bezel setting can conceal minor inclusions around the girdle. A solitaire on a thin band leaves the stone fully exposed. Larger stones, generally above 2.00 carats, demand higher clarity because the viewing area is larger.

Grading Laboratories and How to Read a Clarity Report

The credibility of any clarity grade depends entirely on the laboratory behind it. Three institutions dominate the lab-grown diamond market.

IGI (International Gemological Institute): The dominant grader of lab-grown diamonds globally. IGI issues the highest volume of lab-grown reports and has deep expertise in these stones.

GIA (Gemological Institute of America): The standard-setting authority on the 4Cs. Since July 2020, GIA has graded lab-grown diamonds using identical clarity nomenclature to natural diamonds. A GIA report carries significant weight.

GCAL (Gem Certification & Assurance Lab): Known for its Certified 8X report, which layers optical light performance metrics over standard 4C grading. GCAL also offers a durability guarantee on its reports.

Buyers should look for one of these three laboratories on any lab-grown diamond they consider. In-house or unrecognised certificates may apply softer grading standards, making comparison difficult.

Reading a Clarity Plot

The clarity plot on a grading report is a top-down and bottom-up diagram of the diamond, marked with symbols representing each inclusion type. Red symbols indicate inclusions. Green symbols indicate blemishes. A legend identifies each symbol.

The plot reveals two critical pieces of information. First, the type of inclusion present. Second, its location. An inclusion tucked near the girdle may be hidden by a prong or bezel setting. An inclusion sitting directly under the table, the large flat top facet of the diamond, will be more visible. Understanding the plot helps a buyer choose a stone that looks cleaner than its grade suggests.

Common Myths About Lab-Grown Diamond Clarity

Lab-grown diamonds are flawless by default. Not true. They are grown, not engineered to perfection. Inclusions occur, and lab-grown diamonds are graded on the same scale as natural diamonds.

A beautiful diamond requires an IF or FL grade. False. The visual difference between IF and VS1 is invisible to the unaided eye. The price difference is not.

SI-graded diamonds are always visibly included. Incorrect. Many SI1 lab-grown diamonds are eye-clean, particularly in brilliant cuts. The key is selection, not the grade alone.

IGI grading is softer than GIA. Both laboratories apply the identical scale. Individual grader interpretation can vary at either institution. A well-graded IGI stone is no different from a well-graded GIA stone.

Clarity does not matter in lab-grown diamonds. This is also false. Stones vary in clarity just as natural diamonds do, and clarity meaningfully influences how a diamond looks under light. The difference is that a high clarity lab-grown diamond is more accessible than its natural counterpart.

Conclusion

Clarity is one note in a four-part harmony alongside cut, colour, and carat. But within that harmony, a practical hierarchy emerges.

VS1 to VS2 suits most buyers: reliably eye-clean across shapes and sizes, with a clear price advantage over VVS and IF grades. SI1 is the considered value choice for brilliant cuts, provided the inclusion plot is reviewed. VS1 or higher is the right answer for emerald, Asscher, and other step cuts, as well as stones above 2.00 carats. Grades I1 through I3 are best avoided for fine jewellery.

The diamond is meant to be worn, lived in, and seen at conversational distance. Not under a loupe. Choose a clarity grade that disappears at arm's length. Everything beyond that is certificate prestige.

FAQs on Clarity for Lab-Grown Diamonds

What is the best clarity grade for a lab-grown diamond?

VS1 to VS2 suits most buyers: reliably eye-clean across shapes and sizes, with a clear price advantage over VVS and IF grades. SI1 is the considered value choice for brilliant cuts; VS1 or higher is recommended for emerald and other step cuts.

Do lab-grown diamonds have inclusions?

Yes. Lab-grown diamonds are crystals grown in a laboratory and contain inclusions just as natural diamonds do. The inclusion types differ, but the clarity scale used to grade them is identical.

Is VVS clarity worth the price in a lab-grown diamond?

For most buyers, no. VVS1 and VVS2 inclusions are extremely difficult to see even at 10x magnification, let alone to the wearer's eye. The premium over VS1 buys certificate prestige rather than a visible difference.

What clarity is considered eye-clean in a lab-grown diamond?

VS2 is reliably eye-clean. SI1 is frequently eye-clean, particularly in round and other brilliant cuts. SI2 is variable and should always be reviewed via the clarity plot or high-resolution imagery before purchase.

Are lab-grown diamonds higher in clarity than natural diamonds?

On average, yes. Lab-grown polished inventories tend to skew toward VS and higher because growth conditions can be controlled, and lower clarity rough is more often diverted to industrial use.

What clarity should an emerald cut lab-grown diamond be?

VS1 minimum, ideally VVS2. The long step cut facets of an emerald cut create a window-like effect which exposes any inclusion, so spending up on clarity produces a noticeably more refined result.

How is lab-grown diamond clarity graded?

Under 10x magnification by a trained gemologist at a recognised laboratory, most commonly IGI, GIA, or GCAL. The grader assesses the size, number, position, nature, and relief of inclusions and assigns one of eleven grades from Flawless (FL) to Included 3 (I3).

Does the growth method (HPHT or CVD) affect clarity?

Slightly. HPHT diamonds are more likely to contain metallic flux inclusions, while CVD diamonds more often show graphitic pinpoints or growth striations. Neither method has an inherent clarity ceiling. Both can produce diamonds ranging from Flawless to lower grades.