Shape Guides

Round Cut Diamonds: Classic and Timeless

White diamond against a white background with a white gold or platinum metal

Round diamonds are the most desired of all the shapes, and because of this they also have a few distinct advantages.

To begin with, the pervasiveness of round diamonds means that there are lots to choose from. Diamond manufacturers are acutely aware of the draw of round diamonds compared with other shapes.

In fact, round diamonds are the bread and butter of the diamond industry, and so manufacturers will often choose to cut a rough stone into a round shape (rather than say, a princess shape) even if it means losing some carat weight in the process. They realize that a smaller sized round diamond will sell faster than a larger princess stone. For this reason, every online and offline store will have an expansive selection of round diamonds for you to pick from, meaning you have a very high chance of picking something pretty darn amazing.

The other major advantage of having rounds at the top of the desirability scale, means that there is a huge amount of research done on what exactly constitutes a perfect round diamond. You will find a wealth of information on the best cut dimensions, clarity and color options for rounds (lots on this website so go look!) - Much more in fact, than for any other shaped diamond. This means you are armed with an impressive arsenal of knowledge as you delve into the fantastic (but also slightly bizarre) world of diamonds.

Researching round diamonds: Knowledge is Power

This wealth of research also means that diamond cutters have identified the exact proportions that optimize the sparkle of a round diamond, making it even easier to cut a diamond in a way that is most pleasing to the human eye. Thanks research!

Ideal Round Diamond Stats:

Table width percentage between 54%-60%

Depth percentage between 59%-63%

Crown angle between 33%-35%

Star length of 50%

Girdle of 2.5%-4%

Girdle thickness of Thin to Thick

Rounds and the 4Cs

The other massive draw of the round diamond of course, is the fact that you can get away with much warmer colors (even as low as J and K if you don’t mind a tiiiiiiny hint of a warmth) and much lower clarity grades (go for SI1 all the way down to I1 if you are brave), as round brilliant cut diamonds are awesome at disguising hints of color and small flaws.

Flawless diamond compared to SI1 diamond

This means that you have much more freedom to play around with different combinations of color, clarity and carat than you would have with the other diamond shapes. Hurrah!

Now, so far, we’ve learned that round diamonds are great, but what are the down sides of opting for a round stone?

There are none.


OK, OK! There is one downside. Round diamonds tend to be more expensive than their fancy-cut counterparts (like princess and emerald), simply due to the fact that they’re in much higher demand. Simple economics folks! I didn’t want to say that though, because honestly, I just wanted to end on a more dramatic note.

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