Why Round Brilliant cut diamonds remain the most popular choice...

Round Brilliant cut diamond


Round Brilliant cut diamonds, often called ‘Round diamonds’, or ‘Tolkowsky’s cut’, are the most expensive cuts, and with good reason. They are what is called an ‘Ideal cut’. Cutting an unpolished stone into any other shape usually allows more carat weight to be retained, but the Round Brilliant cut is designed to reflect almost all the light that touches it.

Besides, it takes a diamond cutter 4 to 5 times as long to cut a Round diamond to ideal proportions for the highest polish and symmetry ratings than it does to cut a diamond to average cut parameters.

Even though Round Brilliant cut diamonds are the most expensive in the market, they make up the overwhelming majority of diamonds found in engagement rings, and are popular as stud earrings and in pendants. Today, these loose diamonds account for more than 75% of all diamonds sold.


Best Selling Round Cut Diamond

James Allen is the TOP Rated Online Diamond Retailer

Round Cut Diamond Ring Setting



Ideal Proportions

The Round Brilliant cut is the only cut that has its ideal proportions clearly defined as follows:

Depth: 59% of the diamond; table: 53%; crown height: 16%; pavilion depth: 43%; girdle thickness: medium and even all the way around the diamond; perfectly aligned and formed facets; and very small or absent culet.

If you are unsure about the terms, check out diamond terminology.

The Round Brilliant cut is designed to maximize the brilliance of the diamond, making the stone appear to sparkle and dance in the light. It has traditionally been the choice for engagement and wedding rings, and is ideal for today’s popular vintage settings.

Useful tips

  • The Round Brilliant cut is the most versatile of all the diamond shapes because it can be used in several types of jewelry and in countless styles. The round shape complements almost every design or setting, from classic solitaires to the most avant-garde designs.

  • Apart from individual stones, the Round Brilliant cut is highly popular as a center stone and as side stones in both modern and vintage jewelry.

  • If your Round Brilliant diamond has an Ideal cut or a Very Good cut, the setting should not be strong, but minimal, so that most of the diamond is exposed to the light.

Round Brilliant cuts can be set into four or six prongs, based on the design of the setting, or into a bezel mounting, which is a metal band that runs around the edge of the diamond to hold it securely in the setting.

Loose Diamonds Home   Diamond Basics   Standard Cuts   Fancy Cuts   Bargain Buys