Pear and Marquise Diamonds Also Get Bow Ties: What Fancy-Shape Buyers Must Know

The Bow Tie Problem Is Not Oval-Specific

Most buyers who research the bow-tie effect discover it while shopping for an oval diamond. That makes sense — ovals are among the most popular fancy shapes right now, and the bow tie comes up in almost every oval buying guide. But focusing the conversation on ovals alone leaves out two shapes that are just as susceptible: the pear and the marquise. Both carry the same optical liability, and in the case of the marquise, the risk tends to be even more severe.

The bow-tie effect is a dark, shadow-like band that stretches across the width of a diamond’s center. It appears as a dark, shadow-like pattern that stretches across the width of elongated fancy-shape diamonds when certain pavilion facets reflect the viewer instead of returning light. Bow ties are not an inclusion — they are simply a visual characteristic that happens in elongated fancy shapes. The physics behind it is straightforward: when you lean in close to an elongated diamond, your head and shoulders block part of the incoming light, and the facets that would have reflected that blocked light instead produce dark patches — because of the stone’s elongated geometry, those patches tend to line up horizontally across the center in a shape that looks like a bow tie.

The elongation inherent to oval, pear, and marquise shapes tends to produce a bow tie as part of the visual pattern for most choices of brilliant faceting arrangement and wide ranges of proportions. That finding comes from a GIA paper published in the fall 2024 issue of Gems & Gemology, representing ten years of research on these three shapes. The takeaway for buyers: no matter which of these three shapes you choose, the bow tie is a factor you need to evaluate — not something you can sidestep by picking one shape over another.

How the Effect Differs Across the Three Shapes

Oval, pear, and marquise diamonds share the same root cause for their bow ties, but the way the shadow manifests is a little different in each.

Oval diamonds are probably the most forgiving of the three. In an oval diamond, a subtle bow tie can actually enhance the elongated silhouette that makes the cut so appealing in the first place, giving the stone a quiet sense of character that a uniformly sparkly stone might lack. That said, ovals with a strong, persistent bow tie lose that benefit quickly. The area of dark contrast seen through the table across the width of the stone can vary from slight to thick, and it may be made up of disjointed segments or form a continuous dark bar. For ovals, gemological sources suggest targeting a depth of 57–62%, a table of 53–64%, and a length-to-width ratio of 1.40 to 1.50 to manage bow-tie intensity.

Pear diamonds present a slightly different challenge because of their asymmetric outline. The bow tie appears in pear-shaped diamonds as a dark shadow across the widest part of the stone, near the rounded end. Because a pear combines a rounded half with a tapered point, the effect tends to concentrate where the body is broadest. The asymmetric silhouette can make the shadow look uneven, with one side appearing darker than the other. For pear diamonds, a table percentage of 53–63% and a depth of 58–64% are widely recommended starting points, though the symmetry of the rounded shoulder and the sharpness and centering of the point matter just as much as raw numbers.

Marquise diamonds are where the bow tie conversation gets most urgent. Marquise diamonds carry the highest risk of a severe bow tie, followed closely by ovals and pears. The narrow, pointed silhouette of a marquise concentrates light leakage into a tighter central zone, making even a mild bow tie more visually obvious than in wider shapes. Due to their elegant and elongated shape, nearly all marquise diamonds contain a bow-tie effect, and the dark space stretching across the diamond’s center can impact the beauty of the stone. For marquise cuts, a depth of 58–62% and a table of 53–63% are the generally accepted ranges, with a length-to-width ratio somewhere between 1.75 and 2.25 depending on personal preference for how elongated the stone looks on the finger.

One thing all three shapes share: a bow-tie effect of some degree will almost certainly appear in fancy cuts like ovals, marquises, or pears, and fancy-cut diamonds without any traces of bow ties are usually cut to poor proportions and have issues with brilliance. The goal is not a bow-tie-free stone. The goal is a stone where the shadow is subtle enough to blend into the stone’s character rather than dominate it.

Why the Certificate Won’t Save You

This is the part that catches buyers off guard. The bow-tie effect is not assessed in the 4Cs and will not appear anywhere on a GIA or other grading report. A diamond’s certificate tells you its carat weight, color grade, clarity grade, and cut grade — but nothing about whether that specific stone has a visible bow tie or how pronounced it might be.

Diamond labs like GIA, IGI, or HRD only assign the cut grade for round diamonds. There is some progress on this front: in September 2022, IGI began including a cut grade on reports for loose fancy-shaped diamonds, and this system incorporates shape-specific considerations including the bow tie for ovals, marquise, and pear shapes. But IGI does not grade bow-tie severity as a standalone metric, so even an IGI-certified stone with an Excellent cut grade can still display a prominent bow tie.

What the certificate does tell you that matters: polish and symmetry grades. For all three shapes — oval, pear, and marquise — Excellent or Very Good symmetry and polish are the minimum worth considering. Even a 1–2° angle deviation in critical pavilion facets can turn a mild bow tie into a severe one. Symmetry grades are the closest proxy a grading report gives you for bow-tie risk, even if they don’t predict it with certainty.

Beyond the certificate, visual inspection under varied lighting, 360-degree video, or advanced imaging tools like ASET remains the only reliable detection method. If a vendor cannot provide video of the stone from multiple angles, that is a meaningful gap. One of the simplest ways to identify the bow-tie effect is through a visual inspection — hold the diamond under various lighting conditions and angles to see if a dark bow-tie-shaped shadow appears across its center. Bright overhead light will often hide a bow tie that becomes obvious under diffused or ambient light, so testing under more than one condition matters.

The Proportions to Target — and What to Watch Out For

Proportion ranges for fancy shapes are guidelines, not guarantees. Two stones with identical depth and table percentages can look completely different because of subtle differences in how the pavilion facets were cut and polished. That said, staying within reasonable ranges meaningfully reduces the odds of landing on a stone with a severe bow tie.

Staying within proven proportion ranges — 1.30 to 1.50 for ovals, 1.40 to 1.60 for pears, 1.75 to 2.25 for marquise — helps control severity, but no single metric guarantees a bow-tie-free stone. On the depth side, shallow-cut diamonds let excess light escape from the bottom, while deep-cut diamonds trap light, creating darker areas — both extremes worsen the bow tie. For marquise specifically, cutters sometimes cut deeper to try to diminish the bow tie, but going too deep simply trades one optical problem for another: a dull, lifeless stone.

As the gap between length and width increases, the bow tie often darkens due to more challenging pavilion angle control. This is worth keeping in mind if you are drawn to a very elongated marquise or an extra-slim pear. The more extreme the ratio, the harder it is for a cutter to manage the central facets, and the more likely you are to see a pronounced shadow.

For pear diamonds specifically, symmetry plays a vital role — a pear cut diamond should have evenly rounded shoulders, a sharp and centered point, and no noticeable unevenness. An off-center point or uneven shoulders will almost always produce an uneven bow tie, with one side of the stone looking darker than the other. And for marquise diamonds, meticulous attention should be directed toward symmetry, achieving near-mirror imaging between the right and left sides, coupled with precise alignment of both ends — even a slight misalignment could detrimentally impact the diamond’s aesthetic appeal.

One nuance worth knowing: some bow ties are persistent, while others brighten during motion of the diamond. A bow tie that disappears when the stone moves is far less disruptive than one that stays dark regardless of angle. This is another reason why video is more useful than static images when evaluating a stone remotely.

How to Evaluate Before You Buy

Buying a pear, marquise, or oval diamond without seeing it in motion is a genuine risk. The grading report tells you what the stone is made of; it does not tell you how it looks. Here is a practical approach for evaluating any elongated fancy shape:

First, prioritize Excellent symmetry and Excellent or Very Good polish on the grading report. These grades do not guarantee a minimal bow tie, but poor symmetry grades are a reliable warning sign.

Second, request 360-degree video under at least two lighting conditions. Look specifically at the center of the stone as it rotates. A bow tie that persists through the full rotation is more problematic than one that flickers in and out.

Third, check whether the bow tie is centered and even. In a pear, an off-center shadow suggests asymmetry in the cut. In a marquise, a bow tie that is heavier on one side than the other points to the same issue.

Fourth, as a rule of thumb, the less bow tie the diamond has, the more it will sparkle — but bow ties are not necessarily bad if they are more subtle, like a faint shadow, as this can have little to no impact on the beauty of the diamond.

Fifth, be skeptical of any vendor who tells you a dark bow tie is a feature rather than a flaw. Some jewelers will claim that dark bow ties are actually more appealing and that dark bow ties are inevitable in fancy shapes — this is not true, and very often unethical jewelers are willing to say anything to offload poorly cut diamonds onto unsuspecting consumers.

Because lab-grown diamonds cost less per carat than mined stones, buyers shopping in this category have a practical advantage: lab-grown diamonds exhibit the same bow-tie effect as natural diamonds, and the bow tie is a function of cut quality, not origin — but because lab diamonds are less expensive, you can more easily afford to be selective and choose only stones with minimal bow tie. That selectivity is exactly what the bow-tie evaluation process demands.

At Ouros Jewels, all three shapes — oval, pear, and marquise — are available as loose IGI-certified lab-grown diamonds and as finished rings, including eternity bands featuring marquise and pear cuts that are handcrafted to EF/VS standards. The team’s focus on cut quality and stone selection means bow-tie evaluation is built into the sourcing process, not left to the buyer alone to figure out after the fact. If you are working through a custom design or want to compare specific stones, their showrooms in NYC and London are set up for exactly this kind of side-by-side evaluation under real lighting conditions.