Why Do Diamonds Glow in the Dark?

Learn why some diamonds emit visible light when exposed to long-wave ultraviolet (UV) rays from sources such as the sun. Understand diamond fluorescence, how it affects the value, and how it can improve diamond color.

Why Do Diamonds Glow in the Dark?

Fluorescence is the phenomenon of emitting visible light when an object is exposed to long-wave ultraviolet (UV) rays from sources such as the sun. This can cause some diamonds to emit a bluish light, or more rarely, a yellow or orange light. It's important to understand diamond fluorescence and how it affects the value of diamonds when you're looking to buy one. We'll try to guide you through the diamond fluorescence and get to the bottom of it. Fluorescence in diamonds is the brightness that can be seen when the diamond is under ultraviolet (UV) light.

About 30% of diamonds will shine under UV light, and when exposed to ultraviolet light, there will be a diamond that will emit different colors. The Gemological Institute of America (GIA) rates diamond fluorescence as None, Weak, Medium, Strong and Very Strong. Think about how UV light makes your whites look whiter and your blacklight posters shine. In the same way, some diamonds fluoresce when under UV light. Does fluorescence improve diamond color? It can, but it depends on the strength of the fluorescence.

Strong blue fluorescence in diamonds can cause them to appear hazy or oily under normal lighting conditions. If you've done your homework and googled diamonds for fluorescence, you may have read about a certain GIA study that claims that even strong blue is almost always completely undetectable to the average diamond consumer. When comparing diamonds to each other, you will definitely see a difference between a diamond with a strong fluorescence and one with little or no. It's also important to note that this extreme level of haze for a fluorescent diamond is also not typical and is not as common as you might think when talking about diamonds that are H and below. Some studies done on fluorescence make a statement that is correct: Fluorescence generally improves the appearance of color in diamond. As a final recommendation, if you are buying a diamond with an H color or lower, look for a diamond with medium blue fluorescence. A fluorescent medium blue diamond can even help counteract any yellowish tint diamonds may have and can make them appear much whiter.

In effect, this will cause the color and appearance of the diamond to have a higher color grade. Fluorescence can cause diamond to shine brighter than a diamond that lacks fluorescent properties. It will be more affordable, and since you are there in person, you can see for yourself if the diamond exhibits haze or milkiness. Be sure to ask to see the diamond in a variety of different lighting settings, if possible. Diamonds glow with black light due to a phenomenon called fluorescence, and approximately 35% of natural diamonds exhibit some degree of this effect. In nature, the presence of certain chemical impurities within the diamond composition triggers this brilliant effect in the presence of an ultraviolet light source. Diamonds that belong to a group called type IIB tend to appear blue.

However, after absorbing high-energy light, such as UV light, type IIB diamonds glow in the dark for a short period of time. This residual glow refers to the phosphorescence of a diamond, whose color varies from blue to pink and fiery red, depending on the diamond. Basically, it's a blue light that some diamonds show when they're exposed to UV rays. And fluorescence is the intensity or strength of that blue. Blue only lasts as long as UV light shines on the diamond.

The light goes out and you can't see the fluorescence anymore. Depending on the specific recipe and alloys used in their cultivation process, laboratory diamonds may show rarer fluorescence colors such as yellow-orange or white compared to natural diamonds. The downside to buying a diamond with fluorescence is that you can end up with a hazy or hazy looking diamond. When it comes to buying diamonds with fluorescence, Brian Gavin is a retailer known for its unique super-ideal cut diamonds. If you've done your homework and googled diamonds for fluorescence, you may have read about a certain GIA study that claims that even strong blue is almost always completely imperceptible to the average diamond consumer. Because each and every diamond is different, scientists realized that they could use the color of the glow and how quickly it fades away as an indication of its quality. Next month at the Luxury show in Las Vegas, Russian diamond miner expects to stimulate a similar increase in demand for its new consumer-oriented brand Luminous Diamonds. Before buying a diamond, get personal buying advice from industry veterans.

We'll help you get the best diamond for your money.

Jerome Tarrants
Jerome Tarrants

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