Why flawless natural diamonds are nature’s miracle

The word ‘flawless’ gets thrown around a lot. A flawless complexion, a flawless performance, a flawless red carpet look. When it comes to diamonds, though, the word carries a far more precise meaning.

In fact, it also answers an interesting question: what’s the highest diamond clarity a diamond can achieve? In gemological terms, the answer is simple. Flawless, marked with a capital F.

Most polished diamonds over 30 points (about 0.3 carat) come with a grading report from an independent institute. This report confirms whether the gem is natural or lab-grown and evaluates it according to the 4Cs of diamonds, the global standard for assessing diamond quality.

Diamond cut: Cut refers to how a diamond’s facets are shaped and arranged, a process known as diamond cutting. A well-cut diamond reflects light beautifully, creating its signature brilliance and sparkle¹.

Diamond color: Color measures how much hue appears in a diamond. The GIA’s D to Z grading scale ranks diamonds from completely colorless (D) to light yellow (Z)².

Diamond clarity: Clarity refers to the tiny internal inclusions and surface blemishes formed as a diamond developed deep within the Earth³.

Diamond carat: Carat measures a diamond’s weight. One carat equals 200 milligrams⁴, a detail that often comes up when considering what size diamond for engagement ring might feel right.

A diamond graded Flawless (or FL for short) has no visible inclusions or blemishes when examined under 10x magnification. Put simply, it’s sheer perfection.

What is a Flawless (FL) diamond?

Since a flawless diamond earns its top-tier grading by having zero inclusions or visible blemishes, it’s basically as perfect as a diamond can get. But, as we mentioned earlier, recovering a flawless natural diamond is very rare – many gemologists will never see one in their lifetime.

Given that most lab-grown diamonds occupy a narrow range of quality characteristics, the GIA has introduced a more streamlined assessment method for grading them compared to natural diamonds. They will either be classified as ‘Standard’ or ‘Premium’, depending on their quality and craftsmanship, rather than being graded based on the 4Cs of natural diamonds (opens in new window) as natural diamonds are.

What is the Flawless scale?

Understanding where Flawless sits on the scale becomes easier with a quick look at a diamond clarity guide, which ranks diamonds based on the visibility of inclusions and surface blemishes under magnification.

Flawless (FL): No internal or external imperfections visible under 10x magnification. Extremely rare and highly valuable.

Internally Flawless (IF): No internal inclusions visible under 10x magnification, but may have very minor surface blemishes.

Very, Very Slightly Included (VVS1 & VVS2): Minute inclusions that are extremely difficult for a skilled grader to see under 10x magnification.

Very Slightly Included (VS1 & VS2): Minor inclusions visible under 10x magnification, but typically not visible to the naked eye.

Slightly Included (SI1 & SI2): Noticeable inclusions under 10x magnification, and in some cases may be visible to the naked eye.

Included (I1, I2 & I3): Obvious inclusions visible under 10x magnification and usually visible to the naked eye, potentially affecting transparency and brilliance.

How rare are Flawless diamonds?

Fewer than 1% of all natural diamonds are graded FL (Flawless) or IF (Internally Flawless). It’s this rarity and astounding beauty that makes them a covetable ideal in the diamond world and contributes to the historic value of a natural diamond, particularly when exceptional gems appear at auction or in museum collections.

The De Beers Millennium Star, a 203.04-carat pear-shaped diamond that took three years to cut, is one of the largest FL natural diamonds ever graded. Then there’s the Winston Legacy, a spectacular 101.73-carat natural diamond that sold for more than $26 million at auction. It turned heads not just for its size, but for outstanding color and clarity, too, further reflecting the historic value of a natural diamond when rarity, craftsmanship and provenance align.

What is an Internally Flawless diamond?

When gemologists grade diamonds, they’re looking at how ‘clean’ the gem is, both inside and out. The clarity scale or grading system has six categories, based on what can be seen under 10x magnification: Flawless, Internally Flawless, Very Very Slightly Included, Very Slightly Included, Slightly Included and Included.

At the top of the scale are FL and IF:

Flawless (FL): diamonds with no inclusions or blemishes

Internally Flawless (IF): diamonds with no inclusions, only minor surface blemishes

Natural diamonds with these two clarity grades are rare and extremely desirable. They’re often snapped up by collectors or jewelry buyers wanting to own a piece of geological perfection.

That said, diamonds with visible inclusions or blemishes can be just as dazzling and special – arguably even more so thanks to their unique and distinguishable character.

How can you tell if a Diamond is Flawless?

The first tier on the diamond clarity chart is Flawless (FL) and Internally Flawless (IF). A Flawless diamond has no internal inclusions and no surface blemishes when examined under 10x magnification.

Gems of this caliber are exceptionally rare, the kind you’re more likely to see showcased in museum collections than in everyday jewelry.

FL vs IF diamonds: Small details, big implications

While choosing the highest clarity grade might seem like the safest route to a beautiful diamond, the difference between FL and IF rarely translates to what you actually see on the hand.

Both sit at the very top of the clarity scale, yet their distinctions are microscopic. In fact, identifying whether a diamond is FL or IF typically requires powerful magnification and a trained eye. Without a jeweler’s loupe, the difference is virtually impossible to spot.

What happens once a Flawless diamond is set?

Interestingly, once a Flawless diamond is set into a piece of jewelry, it technically loses its flawless grade. Why? Because gemologists assume that the setting process can introduce tiny surface marks. As a result, a diamond that was once graded FL is typically considered Internally Flawless (IF) once mounted⁵.

Internally Flawless diamonds are still remarkably pure. They contain no internal inclusions at all, though they may show a minute surface detail such as a small nick, scratch or extra facet used to identify the gem⁶.

ADIF tip: Many seasoned collectors pay the premium for FL because of its rarity. For everyday jewelry, though, an IF diamond offers virtually identical beauty.

What inclusions and blemishes mean when it comes to diamond clarity

Inclusions are tiny imperfections that occur inside a diamond as it grows over billions of years, deep underground. In scientific terms, inclusions are small parts of uncrystallized carbon, microscopic cracks, or tiny mineral crystals that became trapped during natural diamond formation.

Inclusions are entirely natural, very common and don’t usually affect the beauty of a diamond unless they’re especially large or in an unflattering spot, like right under the ‘table’ (the large, flat surface on the top of a cut diamond), which is where the eye typically lands first.

Blemishes, on the other hand, happen after the diamond is formed, usually during the cutting and polishing process. They’re external and often so minimal they can only be seen under intense magnification.

Selecting your FL diamond: practical recommendations

Flawless diamonds don’t come around often. If you’re considering one for your diamond jewelry collection, a few practical checks will help you choose wisely.

Confirm certification: A grading report from an independent gemological laboratory verifies the diamond’s quality across the 4Cs: cut, color, clarity and carat weight.

See the diamond in person: Don’t rely on the grading report alone. Viewing the gem yourself is the best way to judge how beautifully it performs in light.

Be prepared for the premium: Because of their rarity, Flawless diamonds often command significantly higher prices than diamonds with slightly lower clarity grades.

Balance the 4Cs: Clarity matters, but cut, colour and carat also influence a diamond’s beauty and value. The right balance will help you find the perfect gem⁷.

If FL clarity is your non-negotiable

If only a Flawless diamond will do, focus on sourcing from reputable jewelers who specialize in rare, investment-grade gems. Because FL diamonds are exceptionally scarce, they are often handled by specialists with access to exclusive dealer networks. Most importantly, never purchase a “Flawless” diamond without an independent grading report from a respected laboratory such as the GIA⁸.

Shape-specific notes

Not all diamond shapes treat clarity the same way. Some cuts disguise tiny inclusions beautifully, while others reveal every detail.

• Round brilliant diamonds: With dozens of light-scattering facets, they’re excellent at hiding small inclusions.

• Oval and pear-shaped diamonds: Their brilliant-style faceting creates plenty of sparkle, helping soften the look of minor imperfections.

• Emerald cut diamonds: Sleek step-cut facets act almost like mirrors, meaning clarity becomes far more visible.

• Cushion and heart-shaped diamonds: Their lively sparkle sits somewhere in between, often masking smaller inclusions⁹.

ADIF tip: If clarity isn’t Flawless, brilliant-style shapes like round, oval or pear can keep a diamond looking beautifully clean to the eye.

Comparing flawless natural and lab-grown diamonds

According to the GIA clarity scale, only natural diamonds can be graded as Flawless (FL). LGDs are either classified as standard or premium due to their narrow range of quality characteristics.

Natural diamonds and how they compare to lab-grown diamonds becomes clearer when you consider how they form. The GIA’s decision to grade natural and lab-grown diamonds differently further highlights the significance of the geological anomalies within a natural diamond and the fact that its clarity is solely determined by the Earth’s extraordinary natural processes.

The recovery of a flawless natural diamond, therefore, is so rare; it is a once-in-a-lifetime moment that cannot be replicated elsewhere.

Premium LGDs, conversely, are created in controlled, stringent conditions, specifically manufactured to minimize imperfections. They’re consistent because of the machinery used to produce them.

Flawless by nature, unmatched in meaning

A flawless natural diamond is a real-life geological phenomenon, and in the world of fine jewelry and rare gemstones, it doesn’t get much better. It’s also why flawless diamonds are often chosen for the most meaningful natural diamond jewelry gifts, marking milestones that deserve something truly exceptional.

That said, it’s hard to ignore the distinct beauty that inclusions or blemishes bring to natural diamonds. They ooze character and charm and hold a unique story with every mark. While scarce and widely covetable, flawlessness should not be confused with perfection, which is something that is truly within the eyes of the beholder.

flawless natural diamond in its natural landscape

FAQs

As they are exceptionally rare and independently certified, Flawless diamonds hold strong appeal for collectors considering investing in diamonds long-term. For engagement rings, they offer both rarity and meaning, pairing symbolic value with collectible prestige.

Yes. Brilliant diamond shapes like round scatter light through many facets, helping hide small blemishes. Step cuts such as emerald or Asscher have long, open facets that make clarity more visible.

For step-cut rings, higher clarity grades like IF or FL are often preferred, while brilliant cuts can still look beautifully clean at slightly lower grades¹⁰.

Simple settings let flawless diamonds shine. Solitaire rings place full focus on the center gem, while halo, three-stone and pavé settings add surrounding sparkle that enhances brilliance. Many of these styles have deep roots in the history of diamond engagement rings, evolving over time to celebrate the beauty of exceptional natural diamonds.

Even slight shifts in color can affect how bright a diamond appears, while tiny clarity differences are often invisible to the naked eye. This is why color in natural diamonds adds to their value and rarity, with near-colorless gems being the most prized¹¹.