What Is a Bow Tie in an Oval Diamond — and Should You Avoid It?

You've found an oval diamond with beautiful specifications.

The carat weight is right.

The colour is excellent.

The clarity is exceptional.

Then you look at the video and notice a darker area running through the middle of the diamond.

It looks a little like a bow tie.

Naturally, the first question is:

Is that bad?

Not necessarily.

A bow tie is a pattern of contrast that can appear across the centre of elongated brilliant-cut diamonds, particularly ovals, pears and marquise diamonds. A subtle bow tie can be completely normal and may even contribute attractive contrast. The problem is when it becomes so dark or prominent that it dominates the diamond.

And importantly, you generally can't determine how noticeable a bow tie will be simply by reading the diamond certificate.

You need to see the diamond.

What Is the Bow-Tie Effect?

The bow-tie effect gets its name from the darker shape that can appear across the centre of certain diamonds.

It can resemble:

◀︎ ▶︎

or the two wings of a bow tie meeting in the middle.

You'll most commonly hear about bow ties when shopping for:

• Oval diamonds

• Pear diamonds

• Marquise diamonds

These shapes are elongated brilliant cuts, and their facet arrangements can create areas of contrast across the centre of the stone.

Some diamonds show very little.

Some show a moderate amount.

And some have an extremely obvious dark bow tie.

Does Every Oval Diamond Have a Bow Tie?

Most oval diamonds can display some degree of bow-tie effect or central contrast depending on the lighting and viewing angle.

That's important because customers are sometimes told to look for an oval with absolutely no bow tie.

In practice, that's not always the right objective.

Contrast is part of what allows us to perceive sparkle and movement in a diamond.

If every facet returned exactly the same brightness at the same moment, the diamond could actually appear relatively flat.

The real question therefore isn't:

"Does this oval have a bow tie?"

It's:

"Is the bow tie attractive or distracting?"

That's a much better way to assess an oval.

When Is a Bow Tie a Problem?

A bow tie becomes undesirable when it remains very dark, broad or visually dominant through normal movement.

Imagine looking at an otherwise beautiful oval and immediately noticing a black band across its centre.

If your eye continually returns to that dark area rather than the diamond as a whole, we'd consider that a problem.

An attractive oval should generally feel balanced.

You want light and contrast moving throughout the stone rather than the centre appearing permanently switched off.

A Little Contrast Isn't Necessarily Bad

This distinction is important.

Darkness isn't automatically a defect.

Diamonds need contrast.

Those alternating areas of light and dark help create the pattern of sparkle we see as the stone moves.

A subtle bow tie can therefore give an oval definition and character.

The issue is excessive darkness.

Think of it as the difference between:

pleasant contrast

and

a distracting black band.

We're trying to avoid the second.

Why Do Oval Diamonds Develop Bow Ties?

A diamond's appearance is created by the relationship between its:

• Facet angles

• Proportions

• Length-to-width ratio

• Pavilion structure

• Light environment

• Viewing angle

When you look at a diamond, some facets return light from the surrounding environment while others reflect darker areas—including the viewer.

In elongated brilliant cuts, this interaction can create the characteristic bow-tie pattern.

That's why the effect can also change as the diamond moves.

Can You Tell Bow Tie From the Certificate?

This is one of the most important things to understand.

A grading certificate doesn't give you a "bow-tie grade."

You might have two oval diamonds that are both:

3.00 carats
D colour
VVS2 clarity
Excellent polish
Excellent symmetry

Yet one can have beautiful, even light performance while the other shows a very prominent dark bow tie.

On paper they may look almost identical.

Visually they can be completely different.

This is exactly why we believe diamond certificates should be used as part of the selection process—not as the entire selection process.

Does Excellent Symmetry Mean No Bow Tie?

No.

Excellent symmetry is certainly desirable, but it doesn't guarantee that an oval will have minimal bow tie.

Symmetry grading assesses the precision of the diamond's facet arrangement and overall symmetry.

It doesn't tell you exactly how the diamond will handle light in every viewing condition.

A diamond can therefore have Excellent symmetry and still display a noticeable bow tie.

Does the Length-to-Width Ratio Affect Bow Tie?

It can influence the overall appearance of the diamond, but ratio alone cannot reliably predict bow-tie severity.

This is important.

You may read online that a particular oval ratio will automatically eliminate bow tie.

We wouldn't choose an oval that way.

Two ovals with the same ratio can still display very different light patterns.

Ratio should primarily help you choose the shape you prefer.

A lower ratio produces a fuller oval.

A higher ratio creates a more elongated appearance.

Within your preferred shape, you then assess the individual diamond's light performance.

What Is a Good Oval Diamond Ratio?

There isn't one universally perfect oval ratio because shape preference is personal.

Some customers love a fuller oval.

Others want a distinctly elongated stone.

For many buyers, an oval somewhere around the mid-1.4s to around 1.5 length-to-width range creates an attractive balance, but this should be treated as a preference guide rather than a rule.

The actual shape matters more than chasing a particular decimal.

If one oval has a ratio of 1.47 and looks spectacular while another measures 1.50 and doesn't, we'd choose the 1.47.

Every time.

Can a Bow Tie Make an Oval Look Smaller?

Potentially, yes.

Not because it physically changes the diamond's dimensions, but because a large dark area can reduce the impression of brightness across the face of the stone.

A bright oval that returns light across most of its surface can feel visually expansive.

An oval with a heavy dark centre can feel less lively even if its measurements are excellent.

This is another reason why finger coverage shouldn't be assessed from measurements alone.

Dimensions tell us how large the diamond is.

Visual performance tells us how effectively it uses that size.

Larger Ovals Need Particularly Careful Selection

As oval diamonds become larger, their visual characteristics become easier to see.

A subtle bow tie in a smaller diamond may not attract much attention.

On a 3 or 4 carat oval, a very dark central area can become considerably more noticeable simply because there's more diamond to look at.

This is why we'd pay particularly close attention to:

• Bow tie

• Overall brightness

• Facet pattern

• Dimensions

• Shape

• Ratio

when selecting larger oval diamonds.

Large carat weight magnifies beauty—but it can magnify undesirable characteristics too.

Why Diamond Videos Are So Important

For oval diamonds, video is extremely useful.

A still photograph captures one diamond position under one lighting condition.

A video allows you to see how the diamond behaves as it moves.

We look for questions such as:

Does the dark area disappear and reappear naturally?

Does light travel through the centre?

Does the diamond remain lively?

Is the bow tie subtle?

Or does the same dark band remain dominant throughout the video?

The latter is something we'd investigate carefully before recommending the stone.

Be Careful With Perfectly Lit Diamond Videos

There's another important consideration.

Lighting can dramatically influence how a diamond appears.

A diamond photographed under intense jewellery lighting may look spectacular.

That doesn't necessarily tell you how it behaves in more ordinary conditions.

Likewise, a diamond can sometimes look darker simply because of the photography environment.

This is why we don't like making decisions based on one frozen frame.

Look at the diamond moving.

Look at how different facets respond.

Look for overall balance.

What Does a Good Oval Look Like?

There's no single formula, but when we're assessing an oval we generally want the entire diamond to feel harmonious.

We're looking for:

A pleasing outline

The oval should have an attractive silhouette without awkward shoulders or an uneven shape.

Good face-up dimensions

The diamond should make sensible use of its carat weight.

Balanced contrast

Dark and bright areas should contribute to sparkle rather than dominate the stone.

Lively movement

As the diamond moves, flashes should travel across it.

An attractive ratio

The shape should suit the customer's preference.

And finally:

No single characteristic should distract you from the diamond as a whole.

That's often the simplest test.

Should You Reject Every Diamond With a Bow Tie?

No.

If you reject every oval that displays any bow-tie effect whatsoever, you could reject some extremely beautiful diamonds.

Instead, assess the severity and appearance.

Ask:

Is it subtle?

Does it move?

Does the centre remain lively?

Do I notice the diamond first—or the bow tie first?

That final question is particularly useful.

If the first thing you see every time is a dark bow tie, we'd probably keep looking.

If you see a beautiful sparkling oval and only notice some natural contrast when specifically searching for it, that's very different.

Bow Tie vs Crushed Ice

These are two different characteristics that buyers sometimes confuse.

A bow tie refers to the darker contrast pattern often seen through the centre of elongated brilliant-cut diamonds.

Crushed ice describes a facet appearance made up of many smaller, fragmented reflections.

Crushed ice is particularly discussed with radiant and cushion diamonds.

Neither term automatically means the diamond is bad.

They describe different visual characteristics.

We'll cover crushed-ice radiants separately because that topic deserves its own guide.

Is Bow Tie More Important Than Colour or Clarity?

Once you're comparing high-quality diamonds, it certainly can be more noticeable.

Consider:

Diamond A

3.05ct
D colour
VVS1
Heavy bow tie

versus

Diamond B

3.01ct
E colour
VVS2
Beautiful light performance and subtle bow tie

On paper, Diamond A has higher colour and clarity specifications.

But if Diamond B looks substantially better?

We'd choose Diamond B.

Because the difference between D and E or VVS1 and VVS2 may be extremely difficult to appreciate without controlled comparison or magnification.

A large dark area through the middle of the diamond is something you may see every day.

What Should You Prioritise When Buying an Oval Diamond?

Don't choose an oval using one number.

Consider the complete diamond.

Look at:

• Carat weight

• Face-up dimensions

• Colour

• Clarity

• Length-to-width ratio

• Overall shape

• Bow tie

• Facet pattern

• Light performance

• Videos

And most importantly:

Look at the actual diamond.

Frequently Asked Questions

Is a bow tie bad in an oval diamond?

Not automatically. Some contrast is normal in elongated brilliant-cut diamonds. A bow tie becomes undesirable when it is excessively dark or visually dominates the centre of the stone.

Can you completely avoid bow tie in an oval?

You can find ovals with very subtle bow-tie effects, but searching for absolutely zero contrast isn't necessarily the right goal. Focus on overall brightness and balance.

Does a higher-quality oval have less bow tie?

Not necessarily. Colour and clarity grades don't determine bow-tie severity. Two D VVS2 ovals can have dramatically different bow ties.

Does Excellent symmetry prevent bow tie?

No. Excellent symmetry doesn't guarantee minimal bow tie. The diamond still needs to be visually assessed.

What oval ratio has the least bow tie?

There isn't a single ratio that guarantees minimal bow tie. Ratio influences shape, but individual facet structure and proportions determine how the diamond handles light.

Can lab-grown oval diamonds have bow ties?

Yes. Bow tie relates to diamond shape, facet structure and light behaviour—not whether the diamond is lab-grown or natural.

Are bow ties more visible in larger diamonds?

They can be. As the face-up area becomes larger, visual characteristics such as strong bow ties may become easier to notice.

Should I buy an oval diamond online?

You can successfully choose an oval online, but don't rely solely on the certificate. High-quality videos and individual assessment are particularly valuable with fancy-shaped diamonds.

The Bottom Line

A bow tie isn't something to fear.

It's something to evaluate.

A subtle amount of contrast can be completely normal in a beautiful oval diamond.

What we'd avoid is a bow tie so dark and dominant that it becomes the first thing you notice.

That's why choosing an oval should never be reduced to:

Carat.

Colour.

Clarity.

Ratio.

Or a grading certificate.

At Southern Star Diamonds, we look at the complete diamond—its proportions, dimensions, shape, videos and visual performance.

Because ultimately, you aren't going to wear the certificate on your finger.

You're going to wear the diamond.