Marquise Cut Diamond — The Pointed Brilliant That Maximises Face-Up Size
Marquise Cut Diamond — The Pointed Brilliant That Maximises Face-Up Size
Length-to-width ratios, the bow-tie effect, and protective setting for the points
A marquise cut diamond is a diamond fashioned in the elongated boat-shaped brilliant cut, with two pointed ends and a 56-facet brilliant pattern modified for the elongated outline. The cut, also called the navette, is one of the older fancy shapes and remains a regular component of the diamond engagement-ring and pendant trade. The marquise is chosen primarily for its visual presence: the elongated outline gives a face-up size noticeably larger than that of a round brilliant of the same carat weight, and the pointed ends produce a distinctive silhouette in setting.
Face-up size and weight
A 1.00 carat marquise diamond at typical proportions presents a face-up area of approximately 9.0 by 4.5 mm — significantly more visual coverage than the 6.5 mm round brilliant of the same weight. The trade-off is depth: the marquise pavilion runs deeper relative to its face-up footprint than the round brilliant, and a marquise of given carat weight is therefore thinner in the visible plane than a round of the same weight. The choice between marquise and round at equivalent weight is, in practice, a choice between visual size and visual proportion.
Length-to-width ratios
Commercial marquise diamonds run length-to-width ratios from approximately 1.75:1 to 2.25:1, with the 1.95–2.10 range most generally accepted as well-proportioned. Stones below 1.75 read as stubby and lose the elongation that justifies the cut; stones above 2.25 are increasingly prone to the bow-tie effect and to the visual perception of being too narrow. The choice of ratio is partly aesthetic and partly determined by the rough crystal — cutters select the ratio that maximises yield from the rough.
The bow-tie
The bow-tie is the dark band that runs across the centre of the face-up view of the marquise, perpendicular to the long axis. It is caused by light leakage in the pavilion: at certain pavilion angles and length-to-width ratios, light entering through the table is not returned to the eye but escapes through the back of the stone, producing a dark zone. The bow-tie is present to some degree in most marquise diamonds — and in pear, oval, and other elongated brilliant cuts. The severity varies with cut quality: a well-cut marquise shows only a faint bow-tie that shifts and disappears at different viewing angles; a poorly cut one shows a pronounced dark zone that remains visible regardless of angle.
GIA grading
GIA assigns symmetry, polish, and proportion grades to marquise diamonds but does not, as of 2024, assign an overall cut grade for fancy shapes (round brilliants are the only shape with a GIA overall cut grade). Buyers evaluating marquise cut quality therefore work from the symmetry and polish grades on the report, the proportions table, and direct visual inspection of the stone — particularly for the bow-tie, point symmetry, and the consistency of the curve from point to side. Loose-stone evaluation is the standard practice; mounted stones are harder to grade because the setting can obscure pavilion features.
Setting
The pointed ends of the marquise are the most vulnerable feature — concentrated stress at the points can cause chipping if the points are not protected. The standard protective setting is the V-prong, in which a metal prong is shaped as a V to fully enclose each point; alternative protective settings include the bezel (fully encasing the perimeter in metal), the half-bezel (enclosing only the points), and the chevron prong. East-west marquise settings — in which the long axis of the stone runs across the finger rather than along it — have been a recurring fashion variant since the 2010s.
Position in the market
Marquise diamonds at equivalent quality typically trade at a discount of 10 to 30 per cent against round brilliants of the same weight and grade — the discount reflects the lower demand for fancy shapes generally and the more limited setting options for pointed shapes specifically. Since approximately 2018, the marquise has seen modest renewed popularity in the engagement-ring market driven by interest in less common shapes; the cut remains a regular component of pendant and earring production across all market segments.
In the trade
For dealers, the relevant evaluation points on a marquise diamond are length-to-width ratio (with 1.95–2.10 generally preferred), the bow-tie severity (visual, not on the report), the symmetry of the two points, and the GIA-assigned symmetry and polish grades. The vulnerability of the points should be considered in any evaluation and disclosed in any sale into setting.