Its character
A step cut: rectangular facets running parallel to the girdle, with cropped corners. There is nowhere for an inclusion to hide behind scintillation, so clarity and colour are graded conservatively here and buyers usually move a grade higher than they would on a brilliant. What it gives back is the hall-of-mirrors effect down the length of the stone.
Where the emerald cut comes from
Step cutting is among the oldest faceting styles, descended from the table cuts of the fifteenth and sixteenth centuries. The shape takes its name from the gemstone: the cropped corners were used on emeralds to reduce the risk of chipping a brittle crystal, and the same outline was later applied to diamonds.
The emerald cut became especially popular in the Art Deco period of the 1920s and 1930s, when its clean lines suited geometric design, and it has stayed a classic since.
How a emerald is faceted
An emerald cut is usually faceted with about 57 or 58 facets in long rows running parallel to the girdle, typically three rows on the crown and three on the pavilion. The corners are cut off at an angle, making the outline an elongated octagon.
Instead of sparkle, the step facets create broad planes of light and dark that shift as the stone moves, often called the hall-of-mirrors effect. The large, open table gives a clear view into the stone.
Emerald cut proportions
Ranges most well-cut emerald stones fall within. They narrow the field; they do not replace seeing the stone.
| Measure | Typical range | Why it matters |
|---|---|---|
| Table | 60 – 69% | Too large a table flattens the steps. |
| Depth | 60 – 70% | Very deep stones look small for their weight. |
| Length to width | 1.30 – 1.50 | Around 1.40 is the classic rectangle. |
| Girdle | Thin to slightly thick | Check the cropped corners. |
| Culet | None to small | Step cuts often finish in a short keel. |
| Cut grade | Not graded | Neither GIA nor IGI assigns an overall cut grade to this shape, so these are trade ranges rather than a standard. |
What to look for in a emerald diamond
Proportions matter more here than on most shapes: too deep and the stone looks small for its weight, too shallow and the steps turn glassy. A ratio around 1.4 gives the classic long rectangle, while squarer stones begin to read like an asscher. Because inclusions sit in plain view, the plotted diagram on the report deserves more attention than the clarity grade alone.
- Clarity and the plot
- Inclusions are easy to see through a step cut. Read the plotted diagram on the report and look for anything under the table; many buyers choose VS2 or better.
- Colour
- The open facets show body colour clearly, particularly in the corners. Consider a colour grade higher than for a round.
- Even steps
- The rows of facets should be parallel and evenly spaced, and the corners the same size. Uneven steps show up clearly on a stone this open.
- Windowing
- A shallow pavilion can leave a washed-out area in the centre where you see straight through the stone. Check it in a video or in person.
Setting a emerald
Four prongs at the corners, or double prongs, are traditional. Emerald cuts pair well with tapered baguettes or trapezoid side stones and suit clean, architectural designs.
Emerald size by carat weight
Approximate face-up size at a typical emerald ratio and depth, drawn to scale. Select a weight to see natural stock in that band.
5 mm. Every silhouette is drawn to this scale, at typical proportions.
- Natural emerald diamonds, 0.25–0.49 ct, about 4.4 × 3.1 mm face up
- Natural emerald diamonds, 0.50–0.74 ct, about 5.6 × 3.8 mm face up
- Natural emerald diamonds, 0.75–0.99 ct, about 6.4 × 4.4 mm face up
- Natural emerald diamonds, 1.00–1.49 ct, about 7.0 × 4.8 mm face up
- Natural emerald diamonds, 1.50–1.99 ct, about 8.0 × 5.5 mm face up
- Natural emerald diamonds, 2.00–2.99 ct, about 8.8 × 6.1 mm face up
- Natural emerald diamonds, 3.00 ct and above, about 10.1 × 7.0 mm face up
Diamond carat guide: every shape, price milestones and choosing a weight
Terms used on this page
Each one is defined in full, with what a report prints for it, in the glossary.
- Step cut
- A faceting style of long parallel facets running around the stone like steps.
- Plot
- The diagram on a report marking where each clarity characteristic sits in the stone.
- Eye-clean
- No inclusion visible to an unaided eye at normal viewing distance.
- Window
- A see-through patch in the middle of the stone where light passes straight out of the bottom.
- Length-to-width ratio
- The outline's proportions — length divided by width — which decides how a fancy shape reads.
- Table %
- The width of the table facet as a percentage of the stone's average diameter.
Emerald cut questions
What buyers ask most often before choosing a emerald diamond.
What clarity should I choose for an emerald cut diamond?
Because step cuts show inclusions clearly, many buyers choose VS2 or higher. A lower grade can still be eye-clean, but check the plot and the stone itself rather than relying on the grade alone.
What is the best ratio for an emerald cut?
About 1.30 to 1.50 is typical, with around 1.40 giving the classic rectangle. Squarer stones start to resemble an asscher cut.
Why does an emerald cut sparkle less than a round?
Its long, flat step facets reflect light in broad flashes rather than breaking it into small points. That clean, reflective look is the character of the shape, not a flaw in the cut.