The essentials you must know when choosing a Diamond cut
Jan 08, 2021
The essentials you must know when choosing a Diamond cut

It is no secret that diamonds' Cut is one of the most important 4Cs, not only determining how they look, but also for how much they can go for on the retail market. To make sure you choose the right diamond and one you will always love, it is important that you understand the basics of the Cut grade. Below is a list of all the information you need to know about diamond cuts. As a way of keeping it concise and easy to refer back to later, we have separated our summary into two parts, one for Round diamonds, and the other for all Other shapes.



A fact most people might not know is that Cut grades are officially given only to round diamonds on certificates. Diamond certifiers, like IGI, award the grades, from the highest, Ideal then Excellent, Very Good, Good, and so on depending on how closely they match the established dimensions for that specific ct size. Due to this, Round Diamonds are the only Cut whose dimensions can be compared against a set of ideal measurements derived from mathematical formulas.


It can be difficult to tell, with the naked eye, the difference in sparkle between an "ideal cut" or an "excellent cut" or a "very good cut", but if you compare the top and bottom grades of "ideal cut" and "very good cut", you will notice a noticeable difference in sparkle. The diamond's Cut is the primary indicator of how well it absorbs and scatters light. If it leaks light from the side, as with lower grades of cut, it decreases the diamond's overall sparkle.
There is a slight increase in price as the cut grade goes up, as you might have noticed. As a general rule, if you want to stay within your budget, it is generally recommended to opt for a larger ct stone by sacrificing a cut grade since you can easily see the size. The difference in sparkle can only be observed when compared with other stones.

Consider going for a "very good cut" if you have a budget constraint, as this will allow you to obtain a more affordable stone in the end. Otherwise, stick with an "excellent cut" if you're looking for a diamond with the signature sparkle at a good price.
For an up-close look at the differences in cuts, book an appointment with our New Zealand showroom located in Auckland.

The essentials you must know when choosing a Diamond cut


There is no standard dimension for diamond shapes other than Rounds, since the dimensions and sizes of 'fancy shapes' can vary greatly. For example, there are some Oval diamonds that are more elongated, while others are more round, or Cushion diamonds that are either square or rectangular. Diamond certifiers, therefore, do not award "cut grading" to diamonds other than Round diamonds.


The cut grade is an important factor that customers value because it helps them decide whether or not a particular diamond is right for them. However, since a diamond that is not round will not include an official cut grade, to address this, our top gemmologist at NOVITA DIAMONDS has developed a set of standards derived through our proprietary mathematical formulas to calculate a cut grade for all other shapes of diamonds.
As we can only grade diamonds we personally have access to, we will only award the 'cut' grade to our showroom stones. Unfortunately, we lack the resources to award similar cut grades to overseas diamonds. If, however, you are interested in a stone that is not round and is unavailable in the showroom and would like to learn more about the Cut, please contact us; our gemmologist will be happy to assist you by providing valuable insights on your selection.
Note: When choosing a lab grown diamond is best to go for Ideal cut when buying an IGI and Excellent cut when buying GIA.