Marquise Cut Diamond
The marquise is the elongated, pointed "boat" shape that looks bigger than almost anything else for its weight. Here's how to read its ratio, judge the bowtie, and pick one that lengthens the finger.
Key Takeaways
- The marquise has the largest face-up size per carat of any diamond shape, so it reads bigger than a round or cushion of the same weight.
- Its long, pointed shape makes the finger and hand look longer and slimmer.
- Every marquise shows a "bowtie" — a dark band across the middle. A faint one is normal; a heavy black one is a fault you can see across the room.
- The flattering range for length-to-width ratio is roughly 1.85 to 2.10 (about twice as long as it is wide).
- Symmetry matters more here than on most shapes: the two points must line up exactly, or the stone looks crooked once it's set.
What is a marquise cut diamond?
A marquise is an elongated stone with a curved body and a sharp point at each end — people describe it as an eye, a boat, or a football shape. It carries about the same number of facets as a round brilliant, but stretched out into that long oval-with-points outline. The look is dramatic and a little old-world. There's a romantic origin story too: the cut is usually traced to the court of King Louis XV of France in the 1700s, who is said to have commissioned a diamond shaped after the lips of his companion, the Marquise de Pompadour — which is where the name comes from (International Gem Society). Whether every detail of that tale is true or not, the shape has stuck around for nearly 300 years.
The marquise sits in the elongated family alongside the oval cut diamond. The difference is the ends: an oval is rounded all the way around, while a marquise comes to a clean point on both tips. Those points are what give it the long, finger-lengthening line — and they're also the part that needs the most care in a setting.
Why it looks so big: the largest spread per carat
Here's the marquise's headline feature. Of all the popular shapes, the marquise gives you the most surface area on top — the part you actually see — for a given carat weight. Because the stone is long and fairly shallow, the cutter spreads the weight out across the face rather than burying it deep underneath. A round brilliant of the same weight hides more of its carat below the surface, where you can't see it.
In plain numbers: a one-carat round brilliant measures roughly 6.5 mm across, while a one-carat marquise runs closer to 10 x 5 mm. Same weight, very different face-up look. That's why people who want maximum size for their budget keep coming back to this shape. The comparison below gives a rough sense of how the on-top footprint changes by carat. Treat these as approximate — exact millimetres depend on how each individual stone is cut.
| Carat weight | Approx. marquise size (mm) | Round brilliant for comparison |
|---|---|---|
| 0.50 ct | ~8.0 x 4.0 mm | ~5.1 mm round |
| 0.75 ct | ~9.0 x 4.5 mm | ~5.8 mm round |
| 1.00 ct | ~10.0 x 5.0 mm | ~6.5 mm round |
| 1.50 ct | ~11.5 x 5.75 mm | ~7.4 mm round |
| 2.00 ct | ~13.0 x 6.5 mm | ~8.2 mm round |
The takeaway: a marquise consistently looks a size up from a round of the same weight. If you love the round but want more presence on the hand, see how the two compare in our round brilliant cut diamond page.
The bowtie: every marquise has one
Look down at any marquise and you'll notice a darker band running across the middle, roughly bowtie-shaped. This is the bowtie effect, and it shows up on every elongated brilliant — marquise, oval, and pear included. It happens because the facets across the narrow middle are steeper than the ones along the length, so your head and hand block the light in that zone and it goes dark (GIA).
A faint bowtie is normal and nothing to worry about. The problem is a heavy, solid-black bowtie that swallows the centre of the stone and kills the sparkle there. You cannot judge this from a grading report — you have to look at the actual diamond, ideally in a few different lights. On our bench in Coquitlam we tilt every marquise under the lamp and at arm's length before we'd put it in a ring, because a bad bowtie is the single most common reason a marquise disappoints once it's on the finger.
Why symmetry matters more here
A marquise is one of the least forgiving shapes for symmetry. Because it has two pointed ends and a curved body, your eye instantly catches any imbalance. The two points should sit on a straight line through the centre. The left half should mirror the right half. If one side bulges or one point sits off-axis, the stone looks tilted or lopsided once it's set, and no setting can fully hide it.
So when you compare marquise stones, check that the points align and the wings (the curved sides) match each other. This is also why the points need protection in the mount. The tips are the thinnest, most fragile part of any marquise, and they're the first place to chip. A V-shaped prong on each end is the standard fix, and it's something our goldsmith sets on-site so we can adjust it to the exact stone.
The ideal ratio: roughly 1.85 to 2.10
Length-to-width ratio is just how long the stone is compared to how wide. A ratio of 2.00 means it's twice as long as it is wide. For marquise, the flattering range most jewellers point to is about 1.85 to 2.10 (GIA).
- Below ~1.80: starts to look short and stubby, losing the elegant marquise line.
- Around 1.90 to 2.00: the classic, balanced marquise most people picture.
- Above ~2.15: very long and slim, dramatic but more prone to a pronounced bowtie and more fragile at the tips.
Ratio is partly personal taste, so look at a few side by side before deciding. One worth knowing: GIA does not give fancy shapes like the marquise an overall cut grade the way it does for rounds, so any "ideal cut" claim on a marquise is the seller's opinion, not a lab grade. Trust your own eyes and a jeweller who'll show you the stone, not a line on paper.
Who the marquise suits
The marquise is a strong pick if you want the biggest look for your budget, if you like a vintage or distinctive shape, or if you want to lengthen the appearance of your fingers — the long line does exactly that. It's less ideal if you work with your hands a lot, because those points need minding. If you love the elongated look but want softer, point-free ends, the oval is the natural alternative, and the cushion cut diamond offers a rounder, softer feel altogether. To see every shape lined up against each other, start at our Diamond Shapes Guide: Every Cut Compared, and when you're ready to design the ring around the stone, our custom engagement ring guide walks through settings, metals, and protecting those points.
Frequently Asked Questions
Does a marquise look bigger than other diamonds?
Yes. The marquise has the largest face-up size per carat of the common shapes, because its long, shallow cut spreads the weight across the top. A one-carat marquise (about 10 x 5 mm) looks noticeably bigger than a one-carat round (about 6.5 mm).
What is the bowtie on a marquise diamond?
It's a darker band shaped like a bowtie that runs across the centre of the stone. Every marquise has one to some degree. A faint bowtie is normal; a heavy black one dulls the middle and should be avoided. You can only judge it by looking at the actual diamond, not the report.
What is the best length-to-width ratio for a marquise?
Roughly 1.85 to 2.10 — about twice as long as it is wide — is the range most jewellers consider flattering. Below 1.80 looks stubby; above 2.15 looks very slim and can show a stronger bowtie. It's partly personal taste, so compare a few in person.
Are marquise diamonds fragile?
The pointed tips are the most fragile part and can chip if knocked. The standard protection is a V-shaped prong over each point, which our goldsmith fits on-site. With proper prongs and normal care, a marquise holds up fine for everyday wear.
Does GIA give marquise diamonds a cut grade?
No. GIA assigns an overall cut grade to round brilliants but not to fancy shapes like the marquise. Any "ideal cut" label on a marquise is the seller's own assessment, so judge symmetry, ratio, and bowtie with your own eyes.
Why does symmetry matter so much on a marquise?
Because the eye instantly catches any imbalance in a pointed, elongated shape. The two points must sit on a straight line and the two curved sides must mirror each other. Poor symmetry makes the stone look crooked or tilted once it's set, and no mounting fully hides it.