Quick answer
What should I look for when buying a cushion-cut diamond?
Buy a cushion by comparing the actual outline, symmetry, faceting pattern, dimensions, girdle, color, clarity and sparkle rather than looking for one universal cushion recipe. Cushion diamonds vary from squarish to rectangular and can use different brilliant-style facet arrangements. GIA does not provide its standard overall cut grade for cushions, so actual-stone images or viewing are especially important.
Key takeaways
- Cushions vary substantially in outline and facet arrangement.
- Do not rank cushion brilliant versus modified cushion brilliant as universally good or bad.
- GIA does not give cushions its standard overall cut grade.
- Check symmetry, outline and girdle condition.
- Use actual appearance to judge the sparkle pattern you prefer.
- Compare millimeter dimensions as well as carat weight.
Choose the outline first
Decide whether you prefer a squarer or more rectangular cushion and compare smooth, balanced sides and corners.
Understand faceting terminology
Modern cushions can have different main-facet arrangements and modified versions can add facets. Treat the terminology as descriptive, not a universal quality ranking.
Do not invent a cushion cut grade
Use report evidence such as polish and symmetry plus actual appearance; do not apply the round-brilliant overall cut system to cushions.
Review the girdle
Cushion girdles can vary in thickness, especially around corners. Extremely thin areas deserve attention because of potential vulnerability.
Compare dimensions and carat
Carat is weight; length and width show how the cushion presents face-up.
Evaluate color and clarity
Use the grades with actual-stone appearance rather than maximizing paper grades automatically.
Judge sparkle from the stone
GIA notes cushion sparkle patterns differ from rounds. Compare videos or stones rather than expecting one pattern.
Finish with price and seller terms
Compare similar cushions and include return policy, setting and service in the decision.
CaratSignal Research
Sources and methodology
- Cushion Cut Diamond: An Old And New Classic | GIA 4CsGemological Institute of America · Researched September 28, 2026
This guide follows the approved Wave 2 / Batch 9 editorial pack. Gemological statements are limited to the cited GIA sources and the evidence available for an individual diamond; report details, images, and remote review do not replace physical inspection where it is needed.
Read the research methodology- First published
- September 28, 2026
- Last researched
- September 28, 2026
- Last updated
- September 28, 2026
- Research status
- published