There’s a reason that diamonds are one of the most beloved and coveted stones in the world. They have a beauty and natural shine that is unmatched. And one of the most important things that gives them that fire is the cut grade of the stone.

What Is Cut Grade?

Diamonds are cut into all kinds of different shapes, from round to pear, heart to oval, and more. These shapes are very important, but they’re not the same thing as a cut grade. According to the Gemological Institute of America, the “cut grade [of a diamond] is really about how well a diamond’s facets interact with light.”

There are five different grades a cut stone can earn: excellent, very good, good, fair, and poor. The cut of a stone is the most complicated (and important) piece of the 4Cs of diamond grading. 

What Makes It So Complicated?

When cutting a rough diamond, a jeweler and gemologist must be precise. One wrong angle can throw off the way the stone reflects the light. It can completely change the look of a diamond with a lower grade in clarity or color and can make them look more beautiful. 

The cutter has the tricky job of shaping a stone so that it reflects the light in ways that will be eye-catching while complimenting the stone’s clarity. The facet of a diamond acts as a mirror, reflecting the light in different angles, accentuating the diamond’s natural fire. They also must cut the stone in a way to maintain as much of the carat weight as possible. 

The Proportions of a Cut Diamond

The way a diamond is cut can cause it to have a combination of different proportions which affects the way it reflects light as well as its carat size. While shopping for a diamond, remember to take a look at the measurements of the stone.

A well-proportioned diamond is cut so that each facet is angled and placed in a way that allows the most light to reflect possible. Light will bounce between each facet, causing the stone to reflect light brilliantly. 

If a stone is cut too deep, the light will have a difficult time reflecting off the facets, and will escape out of the bottom of the stone. Shallow cut stones don’t reflect properly, allowing light to enter it at too low of an angle. 

Grading the Cut of a Diamond

During an evaluation, jewelers and gemologists will take a look at a few different factors before grading a diamond’s cut. They look at the width, shape, angle, symmetry, size, and polish of the stone’s facets. It can be a tricky process, but it’s incredibly important. They also base their grade on the craftsmanship of the gem’s cut as well. 

Thinking of selling your diamonds? The GIA-certified gemologists at Ralph Mueller and Associates can help you out. They can evaluate your stone in their on-site lab and provide the highest quotes. Call us at 480.949.9299 to find out more.