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Which Diamonds Shine the Most? The Factors That Affect a Diamond’s Brilliance

by David Weliver

Sparkle, or “brilliance”, is arguably a diamond’s most important quality. But which diamonds shine the brightest? And how can you be sure that you’re buying a diamond that will sparkle, especially if you’re buying online? Learn the factors that affect a diamond’s brilliance and how to narrow your search to include only gems that are guaranteed to dazzle.

A diamond’s sparkle is influenced by three the stone’s “4 Cs” — cut quality, shape, and color. Some diamond shapes are inherently more brilliant than others; it all depends on how the cut diamonds angles and sides (called facets) reflect light.

How a diamond’s cut affects its sparkle

Round diamonds are more brilliant than oval diamonds, because the rounder shape has a greater number of facets and reflects light from multiple angles. Heart-shaped diamond are often less brilliant; they have fewer sides that can catch light. Pear cut diamonds have one of the greatest surface areas of any diamond shapes, which makes them more prone to reflecting light.

The cut quality also has a great influence on how much a stone sparkles. There are six different angles that can be used to cut each facet on a diamond and they all have an effect on the way light bounces off of them. For this reason, cut quality is often considered the most important of a diamond’s 4 Cs when determining a stone’s value. A diamond’s cut quality is evaluated by the proportions of its facets: too deep and light will be lost in the stone, too shallow and it could lose brilliance.

If you’re looking for a diamond that will sparkle the most, then you’ll want to find one with angles cut as close to 20.75 degrees on each facet–but be prepared to pay more for it! Perfectly-cut diamonds are significantly more expensive.

Diamond color and its impact on brilliance

The diamond’s color also has an effect on a gemstone’s sparkle. Diamonds with less color tend to shine more brightly, as they have less absorption than lesser-colored stones. When it comes to a diamond’s brilliance, less color is better.

Other factors that increase a diamond’s sparkle

A diamond’s clarity also affects brilliance, something that the best trained diamond experts out there know all too well. A diamond with inclusions and blemishes will cause light to disperse, which causes the stone to appear less bright.

Something else to keep in mind is that light sources do also make a difference in terms of a diamond’s brilliance or sparkle. Diamonds always shine in a source of light that is white. Bright flashes of white light, when they hit a brilliant diamond and are reflected back towards you, can be nearly blinding! 

A diamond with inclusions and blemishes will cause light to disperse, which causes the stone to appear less bright.

Aside from the diamond itself, how a diamond is displayed or set in jewelry will have a significant effect on how much it shines. A high ring setting that allows light to enter from underneath and reflect light back through the stone, for instance, will make a diamond sparkle more. A pavé setting that is flush with the ring will let less light through the bottom of the diamond. Less light equals less brilliance.

I’ve discussed how three of the 4Cs affect a diamond’s brilliance. But what about size? Does a diamond’s size have any impact on its sparkle? Not really. If anything, smaller diamonds may shine more brightly simply because there is more surface area relative to the diamond’s total weight. The larger the diamond, the further light needs to travel through the stone. You’ll still enjoy lots of sparkling reflections, it just may lack a bit of the “fire” that well-cut smaller stones have.

This is a good reason to consider using your budget to buy a smaller but higher-quality stone rather than a larger stone of average cut, clarity and color.

Which Diamond Cut Has the Most Sparkle? 

Now that we know what affects a diamond’s sparkle or internal reflection, let’s take a quick look at the types or cuts of diamonds that sparkle the most. Well, the cut of diamond that sparkles the most is the brilliant cut diamond, and due to the critical angle at which all of the facets are cut, the internal reflection of light with this cut is unrivalled by any other cut out there. When a brilliant cut piece of diamond jewelry hits white light, it sparkles like nothing else. If you are looking for a huge sparkle, and you want to see those rainbow colors when light hits the stone, a brilliant diamond is what you want. 

What about lab-created diamonds? Do lab-grown diamonds sparkle less than earth-grown diamonds?

Some people may call them synthetic stones, but realistically, they are just as authentic or genuine as the loose stones found in the ground. They shine with the same brilliance and beauty as mined diamonds, but often with a price that is much more affordable.

Do Simulated Diamonds Shine? 

Simulated diamonds generally don’t have that same sparkle or brilliance as natural diamonds. Genuine diamond, due to the material itself, allows for light to pass through and reflect in a way that fake diamonds, such as those made of cubic zirconia, just can’t get close to.

Although a fake diamond might help you save money, it’s a true diamond that you need if you are looking for that amazing sparkle. Yes, there are some artificial diamonds that sparkle, but no matter what it is made of, it just won’t ever get close to an authentic diamond. 

In conclusion, many factors affect how brightly a diamond shines. From the quality of the diamond to how it is mounted, setting and cut.

Understanding what makes a diamond sparkle will help you identify how to balance your budget with buying the most brilliant diamond. It’s always surprising how the hardest stone that is formed under extreme temperatures allows for so much passage of light! There’s just nothing better than watching a well cut diamond sparkling in the light. 

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