What is diamond cut and why does it matter? 

When it comes to diamonds, the “cut” is a term often used – but it’s also one of the most critical factors influencing a diamond’s beauty and brilliance. Want to know more about diamonds, or ensure you get a good deal? Learn more about diamond cuts, what they are, and why they matter. 

What actually is diamond cut? 

In the world of diamonds, the ‘cut’ refers to the way the stone is shaped – and so much more. The cut encompasses the diamond’s proportions, symmetry, and the quality of its facets, which all play a pivotal role in determining how the diamond interacts with light and, ultimately, its overall visual appeal. Basically – the cut means if your diamonds sparkles or doesn’t.  

The 4Cs of Diamonds 

Before we delve deeper into the intricacies of diamond cut, let’s briefly touch on the 4Cs of diamonds, and what they mean. Once you understand how the 4C’s make up a diamond, you’ll be able to get a great deal on your own. 

  • Carat weight: The size of the diamond, measured in carats (the bigger the carat = the bigger the diamond). 
  • Colour: The presence (or absence) of colour in the diamond. The less colour = the whiter and brighter the diamond. 
  • Clarity: The level of imperfections or blemishes within the stone. The fewer imperfections = the better the clarity. 
  • Cut: The quality of the diamond’s facets and how well it reflects light. 

Factors that contribute to diamond cut: 

1. Proportions of the diamond: 

  • Table percentage: This refers to the size of the flat top facet (the table) in relation to the diameter of the diamond. An ideal table percentage ensures proper light reflection. 
  • Depth Percentage: The depth of the diamond (the height of the pavilion) in relation to its diameter. An optimal depth percentage maximises the brilliance. 

2. Symmetry of the diamond: 

  • Facet alignment: A well-cut diamond features precisely aligned facets that create symmetry and enhance brilliance and sparkle. 
  • Polish: The smoothness and quality of the diamond’s surface impact its ability to reflect light effectively. 

3. Light performance of the diamond: 

  • Fire: The dispersion of light into the colours of the spectrum 
  • Brilliance: The white light reflected from the diamond 
  • Scintillation: The sparkle created by the diamond as it moves 

Diamond cut grading: 

Diamond cut is typically graded on a scale ranging from “Excellent” to “Poor.” The Gemmological Institute of America (GIA) is a well-known authority that grades diamonds on unbiased assessments. You will see diamonds graded in the range excellent – poor. An ‘excellent’ cut diamond will exhibit the most brilliance and sparkle, while a ‘poor’ cut diamond may appear dull and lifeless. 

Why diamond cut matters: 

The cut of a diamond directly impacts its appeal and value in several ways: 

  • Brilliance and sparkle: The better cut the diamond, the better the sparkle it produces. 
  • Size: A well cut diamond can make the diamond look bigger than it is, due to well cut proportions. 
  • Value: Diamonds with better cuts are more valuable and will give you a better resale price. 
  • Beauty: Of course, the most important part of the diamond cut: how beautiful it makes the diamond in question. A badly cut diamond will always look worse compared to a well cut one, despite its other specifications. 

Want some more diamond advice? 

Get in touch with our friendly team of experts, who can answer all your diamond questions. Want to know more about other aspects of diamonds? Learn more in our helpful guides, like: What is diamond colour? What is diamond carat? And what is diamond clarity?