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Cushion Diamond

The cushion cut features soft, rounded corners with a square or rectangular outline, resembling a pillow. It blends vintage charm with modern brilliance, offering exceptional fire and a distinctive chunky sparkle pattern.

Overview

The cushion cut has roots dating back over 200 years, making it one of the oldest diamond shapes still in widespread use. Originally known as the 'old mine cut,' the modern cushion has been re-engineered with updated faceting patterns that dramatically improve light performance while retaining the romantic, soft-edged aesthetic that defined antique diamonds. There are two main types of cushion cuts that buyers should understand. The 'chunky' or 'crushed ice' distinction refers to the facet pattern visible when viewing the stone face-up. Chunky cushions display broad, distinct flashes of light similar to a round brilliant, while crushed ice cushions show a more scattered, almost glittery sparkle pattern. Neither is objectively better—it's a matter of personal preference—but buyers should know which type they're getting before purchasing. From a trade perspective, cushion cuts are among the most efficient shapes to cut from rough, retaining 60-65% of the original crystal weight compared to just 40-50% for round brilliants. This efficiency, combined with lower consumer demand relative to rounds, means cushion cuts typically price 25-35% below comparable round brilliants. The cushion's deep pavilion does mean it carries more weight below the girdle, so a 1-carat cushion will appear slightly smaller face-up than a 1-carat round—something jewelers should communicate to clients upfront.

Carat to Millimeter Chart

Approximate face-up dimensions for cushion diamonds at each carat weight.

Carat WeightSize (mm)
0.25 ct3.5 x 3.5
0.5 ct4.5 x 4.5
0.75 ct5.2 x 5.2
1 ct5.8 x 5.8
1.25 ct6.2 x 6.2
1.5 ct6.7 x 6.7
2 ct7.3 x 7.3
3 ct8.2 x 8.2
4 ct9.0 x 9.0
5 ct9.8 x 9.8

Pros & Cons

Advantages

  • +Exceptional fire—often displays more colorful light dispersion than rounds
  • +25-35% more affordable than comparable round brilliants
  • +Soft, rounded corners reduce the risk of chipping
  • +Versatile aesthetic that bridges vintage and modern design
  • +Available in both square and elongated proportions to suit different tastes
  • +Chunky sparkle pattern is distinctive and eye-catching

Disadvantages

  • -Tends to show color more readily than round brilliants—may need a higher color grade
  • -Deep pavilion means face-up size is smaller than rounds of equal carat weight
  • -No standardized cut grade from major labs—quality assessment requires more expertise
  • -Crushed ice vs. chunky distinction can be confusing for consumers
  • -Bow-tie effect can appear in elongated cushions

Buying Tips

  • Decide between chunky and crushed ice sparkle patterns before shopping—they're fundamentally different looks
  • Color shows more in cushions than rounds—stay at H or above in white metal settings
  • For square cushions, look for L/W ratios between 1.00 and 1.05; for elongated, 1.15-1.25
  • Check the depth percentage: stones over 68% depth will look smaller face-up than their carat weight suggests
  • VS2 clarity is typically eye-clean in cushions due to the facet pattern breaking up inclusions
  • Request video to evaluate the sparkle pattern—photos alone can't convey the difference between chunky and crushed ice