What Does the Cut of a Diamond Mean?

Diamond cut refers not to the shape of a diamond (like round or oval), but to the precision of its proportions, symmetry, and polish. These elements determine how well a diamond reflects light — directly influencing its brilliance, fire, and overall sparkle.

In short, the better the cut, the more beautiful and radiant the diamond will appear. It’s the most important factor in a diamond’s visual performance.


Why Is Diamond Cut So Important?

A diamond’s cut controls how light enters and exits the stone. A well-cut diamond reflects nearly all incoming light back through the top, giving it that signature sparkle. Poorly cut diamonds leak light through the sides or bottom, making them look dull, dark, or lifeless — even if they have high clarity and colour.


Diamond Cut Grades Explained

Reputable grading institutions, like GIA, evaluate diamond cut on the following scale:

  • Excellent / Ideal: Maximum brilliance and light return. These diamonds are cut to precise proportions and reflect nearly all the light they receive. The top choice for sparkle lovers.
  • Very Good: Offers outstanding brilliance, very close to Excellent. A more budget-friendly option with minimal visible differences.
  • Good: Reflects a decent amount of light. Not as sparkly as higher grades, but a fair compromise for cost-conscious buyers.
  • Fair: Noticeable loss of brilliance due to poor light performance. These diamonds appear duller.
  • Poor: Low brilliance and no sparkle. These are generally not recommended for fine jewellery.


How to Choose the Best Diamond Cut

When purchasing a diamond, we recommend prioritising cut quality above all else. Even a high-clarity, colourless diamond will lack sparkle if the cut is poor.

Aim for diamonds graded Excellent or Very Good for optimal light performance, especially in solitaire engagement rings. Avoid “Fair” or “Poor” cuts, as they lack the brilliance and elegance that define a beautiful diamond.

At One Mo Diamond, we offer only diamonds with top-tier cut quality — selected for their light, life, and luxury.

Need guidance choosing the perfect cut? Our team is here to help you find a diamond that truly shines.
Contact us at info@onemodiamond.com — we’ll be happy to assist you.