Your partner shines bright like a diamond, and you’re gearing up to slip an important ring on their finger. Have you ever wondered what gives this fine stone its signature sparkle? If you’re new to the world of diamonds, that’s okay! We’re here to walk you through everything you’ll need to know.

What is Diamond Sparkle?

We often use “sparkle” loosely when referring to a diamond’s shimmer. But if you hear the term, it’s likely describing a few related concepts, all of which happen as light hits a diamond.

● Brightness: Whenever your stone moves, white light on the inside and outside of a diamond gets reflected.

● Fire: Unlike brightness, this term refers to flashes of color that are reflected from a diamond. Fire occurs when white light enters the gem, disperses into separate wavelengths of color and exits the stone.

● Scintillation: Flashes of lighter and darker colors that are produced when light reflects off of a diamond’s flat, polished surfaces (aka facets). Technically, this is another word for “sparkle.”

What Makes a Diamond Sparkle?

Now that you understand diamond sparkle, it’s time to tackle the main question. How is a diamond able to reflect white light and these different flashes of color? The simple answer is a gem’s cut — the arrangement and proportion of those flat, polished surfaces we just mentioned. When light enters a stone, it bounces off of the many surfaces/facets, resulting in beautiful, colorful beams.

It’s worth noting that facets are positioned differently in each diamond, and this ultimately impacts a stone’s shimmer. Trained gemologists then study the gems under magnification and rank them on the Gemological Institute of America’s (GIA) cut scale, which is considered the industry standard for grading diamond cuts.

For reference, here’s a full breakdown of the diamond cut scale:

● Excellent: These diamonds give off plenty of white light (brightness) and flashes of color (fire).

● Very Good: These stones are a subtle step down, as they offer slightly less brightness and fire. But to the untrained eye, they look almost as good as “excellent” diamonds.

● Good: These diamonds tend to lack some scintillation and therefore appear a bit darker than the top two grades.

● Fair: In these diamonds, light often escapes through the bottom and sides of the stone, creating even less brightness. But they might still be doable in pieces featuring side stones or diamonds with smaller carats.

● Poor: These gems offer very little scintillation.

What determines where a diamond ranks on the scale? The symmetry of its facets is one factor. Basically, facets reflect light better if they’re closer in size and shape and positioned at more exact angles.

You’ll also want to keep an eye out for gems that are cut too shallow or too deep, as sparkle might be limited. With a shallow diamond, light usually hits the V-shaped, bottom portion of the stone at a low angle. As a result, light exits through the sides of the gem and never gets reflected through the top of the stone. With deep-cut diamonds, light typically hits the V-shaped portion of the gem at a sharper angle. But this causes light to only move through the bottom of the diamond, making the gem duller in the process.

*Pro Tip: Don’t forget about diamond color and clarity! Stones are brightest when they’re colorless and only showing minor imperfections under magnification. But top-notch diamonds can be pretty expensive, so you should ultimately choose one that works with your budget.

Which Diamond Cuts and Shapes Sparkle More?

You’ll likely come across two common types of diamond cuts, one of them being brilliant cut diamonds. These gems feature facets that are arranged to enhance brightness, fire and scintillation. Therefore, they’re typically able to hide imperfections and hints of unwanted color.

Specifically, round diamonds display the most sparkle because they contain nearly 60 facets! That means more opportunities for light to be reflected. This diamond shape is also popular among couples ready to say “I do.” According to a 2021 jewelry and engagement study conducted by wedding planning website The Knot, more than 40% of pairs chose a round center stone for an engagement ring.

As a general rule, most brilliant cut diamonds have round or elongated shapes. For a modern look, ovals are essentially stretched versions of round diamonds and offer a similar level of sparkle. And although princess cut stones boast a square shape, they shimmer almost as much as their round counterparts.

Have a question? We can help!

Gage Diamonds is Chicago's premier jewelry showroom and online retailer of engagement rings, wedding bands, and fine jewelry. We offer a selection of dazzling handpicked diamonds, including certified natural and lab grown diamonds.

We’re committed to helping you find the ring of your dreams. For inspiration, browse our selection of natural and lab grown diamonds, or set up an appointment with a member of our trusted staff at our in-person showroom.

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