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Arrange your visitDiamond Education · Buying Guide
Cushion Buying Guide
A cushion cut diamond combines the modern round brilliant cut pattern with the classic old mine facet style. Typically featuring 58 to 64 facets, these diamonds are characterised by their rounded corners, giving them an elegant, pillow-like appearance. They also showcase vibrant colours from within the gem when viewed from various angles.
Cut
The standards for cushion cut diamonds can vary considerably from other shapes, making personal preference a crucial factor in selecting the right one.
There are two types of cuts for the cushion diamonds, Cushion brilliant and cushion modified brilliant. This terminology still is confusing to the seasoned jewellery veterans. In simpler terms, we like to explain it as a crushed ice look or distinct faceting. There is no one is better than the other situation, people like both. Just a matter of which is more appealing to the eye of the beholder. Please see examples of both below.
Colour
Cushion cut diamonds tend to display more colour compared to round brilliants, but their brilliance and dispersion can help mask this colour. Therefore, we recommend choosing a colour grade of G or higher.
Recommended · G or higher
Clarity
Most VS2 and SI1 cushion cut diamonds will appear eye-clean, as their inclusions are often concealed by the diamond's sparkle and scintillation. However, it is crucial that the diamond is well-cut. Cushion cuts feature a large, open table, making it challenging to find an eye-clean SI2. When considering SI1 and SI2 diamonds, carefully examine the stone to ensure that any imperfections are not large, dark, or located at the centre.
Recommended · VS2 to SI1
GoodGood Examples of the Two types of different cushion
For a square cushion cut, we recommend a length-to-width ratio where the length is between 1.00 and 1.09 times the width. For a more rectangular cushion, opt for a diamond where the length is between 1.15 and 1.50 times the width. The most popular shape is a slightly rectangular cushion with a length approximately 1.10 to 1.20 times the width.
Square
1.00 – 1.09
Most popular
1.10 – 1.20
Rectangular
1.15 – 1.50
Table & depth
61% – 67%
AvoidLarge, dark or centred inclusions showing through the table
Cushion diamond size chart
Cushion is published twice below, and the reason matters. The most common cushion in our inventory is square, but the elongated cut is what sells — and at 2 carats they measure 7.2 mm and 8.5 mm on the long axis respectively. One “cushion” row would be wrong for most of the stones on our own browse page, so find the cut you are actually looking at.
| Diameter | Carat weight | Typical range | Based on |
|---|---|---|---|
| 2.0 mm | 0.041 ct | — | Calculated |
| 2.5 mm | 0.081 ct | — | Calculated |
| 3.0 mm | 0.14 ct | — | Calculated |
| 3.5 mm | 0.22 ct | — | Calculated |
| 3.8 mm | 0.30 ct | 0.30–0.31 ct | 69 stones |
| 4.6 mm | 0.51 ct | 0.47–0.58 ct | 72 stones |
| 5.0 mm | 0.72 ct | 0.66–0.81 ct | 297 stones |
| 5.5 mm | 1.01 ct | 0.81–1.07 ct | 1,436 stones |
| 6.0 mm | 1.06 ct | 1.00–1.28 ct | 2,184 stones |
| 6.5 mm | 1.52 ct | 1.34–1.62 ct | 2,355 stones |
| 7.0 mm | 1.86 ct | 1.53–2.07 ct | 2,365 stones |
| 7.2 mm | 2.00 ct | 1.88–2.29 ct | 150 stones |
| 7.5 mm | 2.07 ct | 1.97–2.53 ct | 3,052 stones |
| 8.0 mm | 2.75 ct | 2.45–3.09 ct | 4,429 stones |
| 9.0 mm | 3.70 ct | 3.06–4.30 ct | 2,583 stones |
| 10.0 mm | 5.07 ct | 4.51–6.07 ct | 1,350 stones |
| 11.0 mm | 7.04 ct | 6.01–8.04 ct | 477 stones |
| 12.0 mm | 8.87 ct | 8.01–10.09 ct | 210 stones |
Rows from 0.30 ct up are the median of our own GIA and IGI certified stones, with the sample size shown and the typical range being the middle 80% of that bucket. Smaller sizes come from our diamond supplier's own book where it carries the shape, and are calculated from the trade weight formula where it does not. Covers 2.0 mm to 12.0 mm. Snapshot 2026-08-30.
| Length × width | Carat weight | Typical range | Based on |
|---|---|---|---|
| 2.0 × 1.5 mm | 0.025 ct | — | Calculated |
| 2.5 × 1.9 mm | 0.05 ct | — | Calculated |
| 3.0 × 2.3 mm | 0.086 ct | — | Calculated |
| 3.5 × 2.7 mm | 0.14 ct | — | Calculated |
| 4.0 × 3.1 mm | 0.20 ct | — | Calculated |
| 4.5 × 3.4 mm | 0.30 ct | 0.30–0.33 ct | 113 stones |
| 5.0 × 3.9 mm | 0.45 ct | 0.38–0.51 ct | 281 stones |
| 5.3 × 4.1 mm | 0.50 ct | 0.47–0.70 ct | 121 stones |
| 5.5 × 4.2 mm | 0.53 ct | 0.47–0.70 ct | 504 stones |
| 6.0 × 4.6 mm | 0.70 ct | 0.61–0.88 ct | 764 stones |
| 6.5 × 5.1 mm | 1.00 ct | 0.78–1.04 ct | 1,175 stones |
| 7.0 × 5.4 mm | 1.05 ct | 1.00–1.20 ct | 1,610 stones |
| 7.5 × 5.8 mm | 1.50 ct | 1.21–1.57 ct | 884 stones |
| 8.0 × 6.2 mm | 1.70 ct | 1.51–2.04 ct | 1,836 stones |
| 8.5 × 6.5 mm | 2.00 ct | 1.76–2.15 ct | 114 stones |
| 9.0 × 6.9 mm | 2.22 ct | 2.02–2.59 ct | 5,060 stones |
| 10.0 × 7.6 mm | 3.07 ct | 2.64–3.40 ct | 4,287 stones |
| 11.0 × 8.4 mm | 4.07 ct | 3.69–4.94 ct | 1,637 stones |
| 12.0 × 9.0 mm | 5.07 ct | 4.64–6.01 ct | 969 stones |
| 13.0 × 10.0 mm | 7.08 ct | 6.10–8.18 ct | 217 stones |
Rows from 0.30 ct up are the median of our own GIA and IGI certified stones, with the sample size shown and the typical range being the middle 80% of that bucket. Smaller sizes come from our diamond supplier's own book where it carries the shape, and are calculated from the trade weight formula where it does not. Covers 2.0 mm to 13.0 mm. Snapshot 2026-08-30.
Cushion is one of the four shapes our diamond supplier's melee book does not carry, so the rows below 0.30ct are calculated from the trade weight formula and labelled as such. For every other shape, and a converter that works both ways, see the full diamond size chart.
How much does a cushion diamond cost?
Choose a carat weight to see what a natural and a lab-grown cushion diamond cost today, or enter your budget to see the size it buys. Each figure is the typical price of the cushion diamonds available through us at the grade shown under the results, worked out every night; follow its link to see the real stones.
1 ct cushion · Natural
about A$5,144
Typical price · based on 123 diamonds available through us
Listed now, at or under this price
1 ct cushion · Lab-grown
about A$1,507
Typical price · based on 497 diamonds available through us
Listed now, at or under this price
At this size, lab-grown costs about 70% less than natural.
Natural: E–F colour, VS2 clarity, excellent cut for rounds. Lab-grown: E colour, VS1 clarity, ideal cut for rounds. GST included.
Put it in an engagement ringTypical prices of the diamonds available through us, updated 11 October 2026. See every shape and size in our diamond price guide.
Compare other shapes
Cushion sits between the round brilliant and step cuts in look. If you're weighing it against a softer rectangular outline, read the Emerald Buying Guide or the Radiant Cut Buying Guide. For a single-page side-by-side across all ten shapes, see our Diamond Shape Comparison. Or jump straight to our engagement ring designs when you're ready to choose a setting.
Common questions
What's the difference between cushion brilliant and cushion modified?
The cushion brilliant has fewer, larger facets that produce a distinct chunky faceting look. The cushion modified brilliant has an extra row of facets on the pavilion that fragments light into a 'crushed ice' texture. Neither is better — it's a matter of visual preference between clear, defined flashes and a soft, sparkling shimmer.Which cushion ratio looks most square?
For a square cushion cut, aim for a length-to-width ratio between 1.00 and 1.09. The most popular shape is a slightly rectangular cushion with a ratio of 1.10 to 1.20; anything from 1.15 to 1.50 reads distinctly rectangular. Calculate length-to-width ratio from the report measurements, or check the listing calculation.Are cushion cuts good value?
Yes — cushion cuts typically cost 15–30% less per carat than a round brilliant at the same colour, clarity, and cut quality. The saving comes from lower wholesale demand, not lower quality. The trade-off is you need to inspect each stone visually for cut quality because cushion doesn't carry a GIA overall cut grade.Do cushion cuts hide inclusions well?
Most VS2 and SI1 cushion cut diamonds appear eye-clean because their sparkle masks inclusions. Their large open table makes it harder to find an eye-clean SI2, so with SI1 and SI2 diamonds carefully check that imperfections aren't large, dark, or centred — those show through the table more readily than in a brilliant round.