The Diamond 4 C's: Cut

Cut refers to how well a diamond's facets interact with light. The cut depends on the proportions, symmetry, and polish to ensure the most return of light possible in the diamond. 

Diamond Anatomy
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Shape vs. Cut

Cut encompasses two important aspects in the diamond and jewellery industry:

Firstly, it refers to the unique shape and style of a polished diamond, such as the exquisite Princess cut or the elegant Marquise cut. For more information on different diamond shapes, please visit our diamond shapes page.

Different Diamond Shapes
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Secondly, within the context of the "4Cs (Carat, Colour, Clarity, Cut),"  cut signifies the relative quality of a polished diamond's proportions and finish. This includes factors like the diamond's symmetry, polish, and the precision with which its facets are crafted.

Diamond Cut Grading Scale

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It's worth noting that cut grades are exclusively assigned to round diamonds in diamond grading reports, while other diamond shapes do not have specific cut grades.

Out of the 4Cs, cut holds immense significance as it directly influences a diamond's visual appeal. The diamond cutter plays a vital role in determining how to bring out the maximum beauty from a rough diamond.

Considered as optical marvels, polished diamonds ideally reflect and refract light in captivating ways, creating a brilliant display for the viewer. Refer to the illustrations below to visualize this captivating phenomenon.

During the diamond cutting process, the skilled cutter carefully studies the rough diamond to strategize the best approach for enhancing its beauty. In addition to maximizing beauty, there is also a commercial aspect involved, where the cutter aims to retain as much weight as possible to increase the diamond's perceived value. However, prioritizing weight retention can sometimes lead to compromised face-up appearance, resulting in either a bulky, small-diameter diamond or a spread-out, wide-diameter one. It's essential to consider minimum diameter recommendations, especially when purchasing round brilliant diamonds. 

Side by side comparison of two Diamonds with different Cut

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Diamonds with cut grades of "Fair" or "Poor" may exhibit certain issues, such as excessively deep pavilions causing light leakage or overly shallow/spread pavilions resulting in a "fish eye" effect. For this reason, we do not work with diamonds with "Fair", or "Poor" cut grades.


Excellent Diamond Cut

Excellent Cut

Good Diamond Cut

Good Cut

Poor Diamond Cut

Poor cut


The process of assigning a diamond cut grade by GIA:

GIA (Gemological Institute of America) utilises seven essential components to evaluate the cut of a round brilliant diamond. These components include brightness, fire, scintillation, weight ratio, durability, polish, and symmetry. By considering these factors, GIA determines the diamond's cut grade, which ranges from Excellent to Poor. The final grade is determined based on the lowest assessment received for five out of the seven components. In simpler terms, if a diamond receives a Poor grade for brightness, its overall cut grade cannot exceed Poor. However, polish and symmetry follow a different assessment method, aligning with GIA's standard grading methodology. For instance, a diamond with Very Good polish and/or symmetry may still achieve an Excellent cut grade.

When you receive a GIA Diamond Grading Report, it provides a comprehensive evaluation of the diamond's cut, along with a diagram illustrating its proportions and relative measurements. Consider this report as an invaluable tool to assist you in selecting a stunning diamond.


GIA Diamond Grading Report