What Makes a Diamond Sparkle?

What Makes A Diamond Sparkle?

When you take a diamond outside when it’s sunny it will light up the whole surrounding area. However, when you take it inside it will seem darker and not as brilliant. The diamond requires light entering into it such as the sun or an artificial light source. So what makes a diamond sparkle as it does?

The amount of light reflected (whatever the material) is related to the refractive index. Generally speaking the bigger the refractive index change the more light is reflected. So if you compare a diamond to a piece of glass cut into the same shape, the diamond will reflect more light and therefore will sparkle more. The more a material bends light, the higher the RI Refractive index. Diamonds have a very high refractive index (about 2.42 compared to about 1.5 for glass).

The secret that diamonds hold regarding their brightness and diamond sparkle is inside a diamond and is a mix of light refraction, total internal reflection & dispersion.

Properly Cut Diamond

Depending on how a diamond is cut the amount of light that refracts around the internal dimensions of the diamond before exiting through the crown varies. A well-cut diamond will refract the light several times before the light exits displaying sparkle, fire, and scintillation. A diamond is specially cut with facets t give light optimal reflection.

A Poorly Cut Diamond

A poorly cut diamond will allow the light to exit the diamond before it gets a chance to be refracted off the internal facets. This is illustrated in the diagram below. A diamond cut too shallow or too deep will not be as brilliant as a well-cut diamond. Loyes Diamonds only sell diamonds with an excellent cut or a very good cut. This is to ensure the highest levels of brilliance fire and scintillation.

Other factors to consider regarding what makes a diamond Sparkle

There a many factors that contribute to why a diamond sparkles. These include Symmetry and Polish. Read more on our diamond blogs to learn all about Cut, Polish, and Symmetry as these are important attributes featured on the diamond certificate you will receive with each Loyes Diamonds Engagement Ring Purchase.

It is also very important to clean your diamond regularly to ensure maximum sparkle.