6-Main vs. 8-Main Pavilion Facets in Oval Diamonds: Which Reduces Bow Tie More?

The Pavilion Is Where Oval Diamonds Win or Lose

Spend enough time comparing oval diamonds side by side and you notice something: two stones with identical carat weights, the same color, the same clarity grade, can look completely different. One glows from edge to edge. The other has a dark band running through its center that no amount of good lighting can hide. That band is the bow tie effect, and it has almost nothing to do with the certificate in the box.

The bow tie forms because of how light travels through an oval’s pavilion — the lower half of the stone below the girdle. With ovals, the bow tie is light blockage. It means there’s a big shadow that’s being reflected back at you. More specifically, due to the angle of the facets and the way they reflect light, your body and head are preventing the light from ever entering the oval diamond, which leads to the bow tie effect. It’s a geometry problem, not a quality-control failure.

The bow tie is actually made up of a combination of the virtual facets of the pavilion mains and the lower girdles at the belly of the oval. When these virtual facets turn dark because of head shadow and body obstruction, a black bow tie will be visible that can sometimes be very distracting.

The question buyers rarely ask — but should — is which pavilion facet configuration gives the cutter the best chance of managing that shadow. The answer sits in the difference between 6-main and 8-main patterns, and it’s more nuanced than most buying guides admit.

What 6-Main and 8-Main Actually Mean

There are a few options — 4 main, 6 main, and two versions of 8 main patterns. This is how many “main pavilion” facets there are. When you look at an oval from the bottom up, you see a star-shaped pattern. If you look at an oval diamond face up, you’ll notice a star-shaped pattern. The number of “mains” refers to the number of points on that star.

The 6-main configuration places six pavilion main facets around the culet. For a 6-main oval, the azimuths of the lower girdle facets at the ends of the oval have been shifted so that there are four lower girdles that are adjacent to each other on each end of the oval. This shift concentrates lower girdle facets toward the tips rather than the belly, which affects how light distributes across the stone’s widest zone.

The 8-main configuration comes in two distinct versions — typically called Version A and Version B (or “offset”). The two different 8 mains are ones where the arrows go straight through the center and the more common ones where the arrows are offset from the center (this is the majority of ovals you’ll find). In Version A, the star points align directly along the long axis of the oval. In the offset version, those points rotate slightly, redistributing where the virtual facets land at the belly.

There are four standard variations of the oval brilliant cut including two 8-main variations, a 6-main variation, and also a 4-main variation. Both the 6-main and 4-main ovals only have 56 facets. The standard 8-main oval has 58 facets — the same count as a round brilliant — which is part of why it became the dominant commercial cut.

The key mechanical difference: in a 6-main oval, there are no pavilion main facets running through the belly zone. The ends of the oval are handled by lower girdle facets that are steeper by nature. In an 8-main oval, pavilion mains extend through the belly, which means those larger reflective surfaces directly influence what you see in the bow tie zone.

Bow Tie Comparison: 6-Main vs. 8-Main

Here is a direct comparison of how each configuration performs against the bow tie:

Fewer pavilion mains means the diamond is likely to have bigger and bolder flashes of fire due to fewer but larger virtual facets. The opposite is true and you will get more but smaller pin-flashes of fire in an oval with 8 pavilion mains.

From a bow tie standpoint, 6-main ovals have a structural advantage in one specific area: 6 and 4-main ovals have less of this problem because there are no pavilion facets at the ends. Lower girdle facets are steeper than pavilion facets so you get less flatness, but at the same time you lose the structured contrast pattern that the pavilion main offers.

But the 8-main offset pattern has its own argument. Diamonds with an eight-main pattern often exhibit a lively sparkle and can minimize the bow tie effect due to the greater number of facets. The logic is that more facets in the belly zone means more surfaces bouncing light back, statistically reducing the chance that the bow tie zone goes entirely dark. The more facets you have in the middle area, the more light will be reflected back, reducing the chance of a bow tie.

So which wins? The honest answer is: it depends on the individual stone and how the cutter used the pattern. It is not possible to draw reliable conclusions based only on the facet pattern. The reason is that there are too many other variables that combine to affect the ultimate light performance. Pavilion angle, depth percentage, crown angle, and symmetry all interact with the facet count in ways that make the pattern itself a starting point, not a guarantee.

That said, experienced oval buyers tend to develop a preference. Some favor the 8-main offset for its livelier, more dynamic scintillation pattern. 4 mains tends to produce a more “antique” look with broader, chunkier flashes of light. 6 mains is a more balanced approach to sharp/broad flashes of light. 8 mains tends to produce a more “sharp” or pinpoint reflection of light.

The Variables That Matter More Than Facet Count

Facet count sets the stage, but pavilion angle and depth percentage write the actual performance. Even slight deviations in pavilion angle (sometimes less than a single degree) can drastically influence the bow tie’s visibility. A well-executed 8-main oval at the right depth will almost always outperform a poorly proportioned 6-main stone.

Ideal depth (58–63%) balances light reflection, reducing the bow-tie effect. Go shallower than that range and the stone risks leaking light at the belly. Go deeper and you trap light inside, creating darker zones and a stone that faces up smaller than its carat weight suggests. The tricky part is that as you go shallower from the ideal depth of a round, you actually go through a range of pavilion angles where the bow tie is worse before it gets better.

Symmetry is probably the most underrated factor. An oval’s brilliance depends heavily on consistent facet architecture. If opposing facets are misaligned or uneven, the pattern of light and shadow becomes irregular. While perfect symmetry isn’t required, well-balanced precision helps distribute light evenly across the stone, softening any potential bow tie and enhancing the fire.

Length-to-width ratio also plays a role. Above 1.55, the diamond can appear pencil-thin and the bow-tie effect tends to worsen. Most experts recommend staying between 1.35 and 1.50 for the best balance between visual elongation and bow tie control. The length-to-width ratio of an oval diamond can influence its appearance and the bow tie effect. Most experts recommend a ratio between 1.35 and 1.50 for an ideal oval diamond. A longer, narrower oval may exhibit a more pronounced bow tie, while a rounder oval can appear more balanced and may hide the bow tie effect better.

Finally, lab-grown diamonds exhibit the same bow tie effect as natural diamonds. The bow tie is a function of cut quality, not origin. This is worth knowing for buyers shopping lab-grown ovals specifically — the facet pattern discussion applies identically to CVD and HPHT stones.

How to Actually Evaluate Bow Tie Before You Buy

The bow tie is not reported on GIA or IGI certificates. Diamond certificates (GIA, AGS, IGI) do not report bow tie presence or severity. This makes visual inspection critical. You cannot determine bow tie severity from a grading report alone, regardless of how strong the other grades look.

The most reliable evaluation method is a 360-degree video viewed under consistent lighting. A bow tie that disappears as the stone tilts is manageable — often desirable. A strong bow tie will stay dark from every angle. A soft, appealing one will come alive with movement, shifting in intensity, dissolving into sparkle, or disappearing entirely as the diamond tilts.

For buyers who want a more technical read, the ASET (Angular Spectrum Evaluation Tool) provides a color-coded map of light performance. The ASET evaluates a diamond’s light performance using an easy to understand color-coded system. Different colors — red, green, blue, white, and black — represent different light angles. These colors can quickly and efficiently tell you if your diamond’s bow tie is as bad or better than you think it is.

A mild bow tie is not automatically a problem. Contrary to popular belief, a bow tie is not inherently negative. In fact, many of the most desirable ovals have a delicate, understated bow tie that gives the diamond personality, structure, and visual depth. The goal is not a bow-tie-free oval — that stone probably doesn’t exist — but a stone where the shadow adds contrast rather than dominating the center.

At Ouros Jewels, each oval lab-grown diamond in the collection is hand-selected with cut quality as the primary filter. Stones are available with IGI certification, and the team can walk you through 360-degree video evaluation to assess bow tie severity before purchase — exactly the kind of visual review that a certificate number alone can’t replace.

The Recommendation

If the question is purely “which facet pattern reduces bow tie most reliably,” the 8-main offset (Version B) is probably the most practical answer for most buyers. It’s the most widely cut configuration, which means there are more examples to compare, and its rotated arrow pattern tends to distribute the belly shadow more evenly than the straight 8-main Version A. The 6-main pattern has a structural case for lower bow tie risk at the belly — no pavilion mains means no pavilion mains going dark — but it’s rarer in the market and produces a distinctly different visual character that not every buyer prefers.

But facet count is only one input. The honest framework for choosing an oval diamond is this:

• Facet pattern: 8-main offset or 6-main, both are reasonable starting points
• Depth: 58–63% to balance light return without hiding carat weight
• L/W ratio: 1.35–1.50 for the classic oval silhouette with manageable bow tie
• Symmetry: Excellent or Very Good — misaligned facets create unpredictable shadows regardless of pattern
• Visual inspection: Watch 360-degree video; look for a bow tie that moves and softens rather than sitting static and dark

It is possible to minimize the bow tie but it is not possible to eliminate light obstruction completely. Any source claiming otherwise is oversimplifying. The goal is a stone where the bow tie is subtle enough to read as contrast and depth rather than a dark void — and that outcome depends on the cutter’s execution far more than the pattern they started with.

For buyers currently shopping oval lab-grown diamonds, Ouros Jewels offers IGI-certified oval cut diamonds ranging from 0.25 to 11 carats, with options across multiple cut styles. The combination of certification and direct stone review gives buyers the two things that actually matter when evaluating bow tie: documented proportions and a real look at how the stone performs under light.