Marquise Diamonds: buyer checklist
The marquise is a long, boat-shaped brilliant with a point at each end. Its defining characteristic is efficiency: it delivers the largest face-up area of any diamond shape for its carat weight. A marquise looks substantially bigger than a round of the same weight, and costs less per carat into the bargain.
It is also the shape that most rewards knowing what to look for, because three of its critical qualities appear nowhere on a grading report. This page is about choosing the stone. For settings and finished rings, see marquise diamond rings.
The checklist, in order of importance:
- Check the two points align through the centre — asymmetry makes the stone look bent.
- View it face-up for a bow-tie. Every marquise has one; you want it faint.
- Decide your length-to-width ratio deliberately.
- Check the girdle thickness at both points for durability.
- Look for colour gathering at the tips.
- Confirm the setting will have V-prongs before you buy the stone.
The main options to compare
Length-to-width ratio
This is the first decision, and it is preference rather than quality — but it changes the stone completely. Marquise diamonds are commonly cut anywhere from around 1.75 to 2.25 in ratio. A lower ratio produces a fuller, broader stone that reads rounder and covers more width on the finger. A higher ratio produces a long, slender, more dramatic outline that maximises the elongating effect.
Neither is better. But you should decide which you want before looking, because otherwise you will simply take whatever is offered. Calculate it from the measurements on the report: length divided by width.
Origin
Natural or laboratory-grown — the largest single influence on price. Both are diamond, graded identically, and origin must be stated on the report. See lab-grown vs natural diamond.
Alternatives worth considering
If the exposed points concern you, the oval gives similar elongation and similar spread-per-carat with no vulnerable tips. The pear sits between the two, with one point rather than two. Compare all outlines at diamond shapes.
Quality and practical factors: symmetry, bow-tie visibility, tip protection and face-up proportions
Symmetry — and why it matters more here
In a marquise, symmetry is not a technicality. The two points must align with each other through the centre axis of the stone. If they are offset even slightly, the marquise appears bent or crooked, and once you have noticed it you will notice it every time. Look straight down the length of the stone to check.
Check also that the two halves either side of the widest point mirror each other, and that the curved sides are even. Because the shape is long and narrow, any irregularity is magnified visually in a way it would not be in a round or cushion.
The bow-tie
A bow-tie is a dark band running across the width of the stone at its centre, caused by the pavilion facets shadowing light where the viewer’s own head blocks the light source. Marquise cuts show it more strongly and more often than any other shape, because their length makes the effect more pronounced.
Every marquise has some degree of bow-tie. A well-proportioned one shows only a faint shadow that moves and disappears as the stone tilts. A poorly proportioned one has a permanent dark stripe through the middle, which kills the stone’s brightness. It appears on no grading report and no laboratory grades it. The only way to assess it is to look at the stone face-up, in normal light, at arm’s length. This is the strongest argument for viewing a marquise in person, and it is why we will always show you the stone rather than sell one from paperwork.
Tip durability
The points are the thinnest part of the stone and the most likely place for damage. Two things to check. Ask about girdle thickness at the points — an extremely thin girdle there is a genuine durability concern, and it appears on the report. And ask whether either tip shows an existing chip, abrasion or a natural, all of which are common in this shape and should be disclosed.
Whatever the stone, it must be set with a V-prong wrapping each point. This is not a style preference; it is what stops the tips chipping. Decide it before you buy the stone, because it may influence which stone you choose.
Face-up proportions and depth
Ask for millimetre measurements alongside carat weight. The marquise’s advantage is spread, so compare face-up dimensions across candidates rather than weights. A marquise cut too deep loses that advantage entirely — it carries weight below the girdle where nobody sees it, which defeats the purpose of choosing the shape.
Price and budget considerations
The marquise is among the strongest value shapes available, and the saving compounds from two directions: lower cost per carat than a round brilliant, and more visible size per carat than any other shape. A marquise will look considerably larger than a round of identical weight while costing less to buy.
- Diamond origin — the largest lever, as in every shape.
- Carat weight and the round-number thresholds — buying just under a threshold remains the single most effective saving.
- Symmetry and bow-tie quality — a well-cut marquise with true alignment and a faint bow-tie commands a premium. This is the one thing not to economise on in this shape. A cheap marquise is almost always cheap because it is crooked or has a heavy bow-tie, and both are permanent.
- Clarity — the easiest saving. The brilliant faceting hides inclusions well away from the tips. Ask for the plot and check nothing sits near a point or under the centre.
- Colour — worth a grade more than you would accept in a round if setting in white metal, because marquise cuts concentrate colour at the tips. In yellow or rose gold, take the saving.
- Budget for a shaped wedding band if one will be worn alongside — a long north-south marquise will rarely sit flush against a straight band.
See diamond price South Africa for the pricing framework. Quotes are dated and specification-based, since availability moves.
Certification, documentation and trust checks
Marquise diamonds are graded on the four characteristics described in GIA’s grading methodology, with report types set out in GIA’s guide to report types.
- There is no overall cut grade. Fancy shapes are generally reported with polish, symmetry and proportion figures rather than a single cut letter. In a marquise, weight the symmetry grade heavily — it is the closest thing on the report to a proxy for whether the stone is properly aligned.
- Verify the report number on the issuing laboratory’s own database rather than relying on a printed sheet, and check the measurements match the stone.
- Read the origin and treatment lines — natural or laboratory-grown, and any clarity or colour treatment.
- Study the clarity plot, paying particular attention to anything near either point.
- Check girdle thickness, which is recorded and matters more in this shape than most.
- Remember what the report cannot tell you — bow-tie strength, and how the stone actually looks face-up. Those require your own eyes. See diamond certificate explained.
How to assess a bow-tie properly
Since this is the check that matters most and the one no report covers, it is worth doing methodically. Hold the stone face-up at arm’s length in ordinary indoor light — not under a jeweller’s lamp, which floods the stone and hides the effect. Look at the centre of the diamond and compare its brightness with the areas toward each point.
Now tilt the stone gently. In a well-cut marquise the shadow shifts and breaks up as the angle changes, and at most angles the centre is as bright as the ends. In a poorly cut one the dark band stays put — it is a fixed feature of the stone’s geometry rather than a passing reflection, and it will look the same on a hand every day for the rest of the ring’s life.
If you are comparing two stones, put them side by side and look at both centres together. The difference is usually obvious in seconds when you have something to compare against, and almost impossible to judge on a single stone in isolation. This is the single strongest reason to view marquise diamonds together rather than one at a time.
Common mistakes to avoid
- Buying a marquise from paperwork alone. The two things that most determine whether it looks good — symmetry and bow-tie — are not on the report. This is the most common and most expensive mistake in this shape.
- Chasing the cheapest marquise. The discount is usually paying for a crooked stone or a heavy bow-tie.
- Ignoring the ratio. Accepting whatever is offered rather than deciding what you want.
- Accepting a setting without V-prongs. Exposed points will chip.
- Forgetting the wedding band. Discovering after the engagement ring is made that no straight band will fit is an avoidable and costly surprise.
- Comparing on carat weight rather than millimetres. The whole point of a marquise is spread — measure it.
- Overlooking colour at the tips when setting in white metal.
Next step: narrow the shortlist and enquire
Decide your ratio, set your origin and budget, then ask to see two or three marquise stones together. Compare them face-up in normal light for bow-tie, look down the length of each for point alignment, and compare millimetre spread rather than carat weight. Those three checks will separate a good marquise from a poor one faster than any specification sheet.
Then move to settings at marquise diamond rings, or compare shapes at diamond shapes. For the wider process, the diamond buying guide.
Continue to the relevant buying guide or book expert guidance
Tell us the ratio, size and budget you have in mind and whether you want natural or laboratory-grown. We will put several marquise stones in front of you face-up so you can judge bow-tie and symmetry for yourself — the two things that decide this shape and that no report will ever tell you.