Understanding Diamond Cut: The Secret to Maximum Sparkle and Brilliance

Diamond cut refers to how well-proportioned the dimensions of a diamond are and how its surfaces, or facets, are positioned to create sparkle and brilliance. There are several different cuts of diamonds, each describing the quality of the gem’s faceting, symmetry, proportion, and polish. The higher a diamond cut rating, the better that gem’s light performance and symmetry.

Different diamond shapes will have their own ideal faceting and proportions, with balance and brilliance as the most important elements of all diamond cuts. The better cuts of diamonds will have the best light performance, with impressive sparkle and shine.

A diamond’s cut has the biggest impact on its sparkle, with many facets playing into how well-proportioned a diamond is. Explore our guide to learn more about the different types of diamond cuts, diamond anatomy, the diamond cut chart, GIA diamond cut ratings, and how these all impact the price of a diamond.

The Most Important of the 4Cs: Diamond Cut

When it comes to the famous 4Cs of diamonds, cut is considered the most important of them all. This is because a diamond’s cut can impact its beauty, its brilliance, and even how large it appears when worn in jewelry such as engagement rings. The different cuts of diamonds each have their own impact on a gem’s appearance, with higher-quality cuts making diamonds look their very best.

So whether you’re buying natural or lab-grown diamonds, we recommend aiming for the best diamond cut grade your budget allows.


Are You Looking for the Best Diamond Cut? It All Starts With Your Budget

No single diamond is perfect for everyone—but all of our customers, whether they’re eyeing a 0.50-carat or a 16-carat diamond, want as much sparkle as their budget allows. Of the 4Cs (cut, color, clarity, carat), cut has the greatest influence on a diamond’s beauty and sparkle. Even a diamond with a flawless clarity grade (no blemishes or inclusions) can look glassy or dull if the cut is too shallow or deep. So, when determining what diamond to buy, go with the best cut grade that you can afford.


Diamond Cut and Diamond Shape Are Not the Same Thing

Although these terms are sometimes used interchangeably, diamond cut and diamond shape mean different things. Diamond cut assesses the light performance of a diamond and is based on a combination of factors: proportions, symmetry, and polish (the overall surface condition of a diamond’s facets).

What Is the Most Expensive Cut of a Diamond?

When people talk about someone’s engagement ring, everyone focuses on carat. In reality, it’s the cut of the diamond that can be the biggest factor in the price tag. The Ideal cut diamond, and the super-ideal Astor by Blue Nile™, are the most expensive diamond cuts because they optimize light performance and create the most impressive sparkle.

Our loose diamonds are accompanied by certificates and grading reports for their most important qualities. The most popular diamond grading institutions are IGI and GIA.

Diamonds that are accompanied by grading reports are the most highly valued in the industry. Every loose diamond at Blue Nile has been analyzed and graded by respected diamond institutions. You’ll find a diamond certificate on every diamond’s detail page.

Diamond Light Performance and Measurement

Two diamonds cut with optimal proportions won’t necessarily have the exact same light performance or beauty. For this reason, true light performance is measured by the GemEx BrillianceScope® Analyzer, a patented system that uses spectrophotometer technology to compare diamonds with the same shape.

Popular Diamond Cut Styles

While there are specific GIA and IGI ratings for diamond cut quality, the term can also refer to specific faceting styles. You’ll see this with terms such as step-cut diamonds or brilliant-cut diamonds. For these instances, the terms about diamond cuts refer to the faceting technique and what it highlights in a gem.

Step-Cut Diamonds

Step-cut diamonds are diamonds that are faceted with rectangular angles that highlight the gem’s shape and its glow. Popular step-cuts include emerald cut diamonds, Asscher cut diamonds, and baguette diamonds.

Brilliant-Cut Diamonds

Brilliant-cut diamonds are diamonds that are faceted for the most sparkle and fire. They typically have more facets than step-cut diamonds. Popular brilliant-cut diamonds include round diamonds, cushion cut diamonds, and princess diamonds. Elongated diamonds with brilliant cuts, such as marquise diamonds, radiant diamonds, and oval diamonds, are considered modified brilliant-cut diamonds.

Finding the Best Diamond Cut

With so many types of diamond cuts, ratings, and factors, there are many ways to find the perfect fit for your purchase. You can browse our wide array of loose diamonds for sale and sort by diamond cut. Our experts are also available to help you explore the different diamond cuts. Visit one of our nearby jewelry stores or schedule a virtual jewelry shopping appointment to get started. If you have any questions, Live Chat is also available during most business hours.