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Annual March Diamond Madness - Meet Our Champion - Up to 11% Off
Annual March Diamond Madness - Meet Our Champion - Up to 11% Off
A closer look at the round brilliant cut

A closer look at the round brilliant cut

Though there are many different diamond cut options on the market, the round cut has remained a standard. There's good reason for this, as round cuts are given a grade by both the Gemological Institute of America and the American Gemological Society. Round brilliant diamonds also optimize light performance through the precise planning of angles. Here is a closer look at the popular diamond shape:

Terms to know

When assessing a diamond or talking about its structure, there are a few bits of jargon you should have in your vernacular.

Scintillation: This refers to the apparent sparkle in a diamond. This sparkle is the flashes of white or colored light seen when the diamond is in motion. The observer may see patterns created by light. An example of this are the hearts and arrows patterns seen in Brian Gavin's highly graded diamonds.

Brilliance: Also known as brightness, brilliance refers to internal and external reflections of white light in a diamond. Proportions, angles and symmetry cut into a gem are what determine the brilliance. A perfectly cut diamond will have symmetrical facets which reflect light most effectively.

Fire: The phenomenon where white light is split into colors and reflected back on the observer is known as fire.

Leakage: Areas where light escapes a diamond.

Contrast: Expertly cut diamonds reflect areas of white and dark light. The contrast between these is visible, though the dark spots do not detract from the brilliance of the diamond.

Durability: This refers to how resistant a gem is to scratches or chipping.

Extracting beauty

When diamonds are in the rough, they aren't much to behold. It is the cutter who brings out all the qualities for which diamonds are known. That famous sparkle is optimized by the precision a diamond cutter employs. Brian Gavin round brilliant diamonds, specifically the hearts and arrows, have been given an elusive AGS 0 grade for light performance, the best grade possible. When the perfect angles, symmetry and polish have been achieved, you can see eight distinct hearts.

AGS

The AGS grading system for round cut diamonds ranges from ideal to poor - ideal being the best possible grade. Along with the word comes a number. Ideal grades are given a zero. The poorest quality cut is given a 10.

Diamonds are geometric structures that rely on precise angles to reflect and redirect light. Each facet, or face, must be symmetrical to utilize light in the perfect way. Really, it's a mathematical equation in the works. The right formula will create a brilliant play of light. Remember looking in kaleidoscopes as a kid? Round diamonds work in the same way, only they are much more dynamic. For this reason, the AGS utilizes 3D models to assess the performance of each individual facet in a brilliant diamond.

The light you see in a diamond comes from the world surrounding you. The fixtures over your head, the sun streaming from a window, and even the glow bouncing off your t-shirt all enter the diamond. A diamond cut seeks to take that light and direct it in the most beautiful way possible. AGS looks at this when grading for performance. This is also where hearts and arrows comes from.

GIA

The GIA diamond cut grading scale for round cut diamonds is very similar to its AGS counterpart. This method also looks at the diamond's facet and uses computer modeling to predict how the angles will manipulate light entering the gem. Grading also takes into account a diamond's weight relative to its diameter, its girdle thickness - which contributes to durability - the symmetry facet arrangement and the quality of polish on the facets. Grades start at poor, then go to fair, good, very good and excellent.

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