Diamond Fluorescence
When shopping for a diamond, you’ll often hear about the Four Cs—cut, color, clarity, and carat. These are the cornerstones of diamond quality. That said, there are other characteristics that can still influence a diamond’s beauty and value. One of those is fluorescence.
While fluorescence doesn’t impact a diamond as strongly as, say, cut or clarity, it can still affect both appearance and price. That’s why it’s worth understanding what fluorescence is, how it works, and whether it’s something to seek out—or avoid—when choosing your diamond.
In this article, we’ll discuss the ins and outs of fluorescence. We’ll take a look at what diamond fluorescence really means, how it affects visual appearance and value, and what to consider when deciding if it’s right for your next stone.
What Is Diamond Fluorescence?
Diamond fluorescence refers to the glow that some diamonds give off when put under ultraviolet (UV) light. The most common colour of fluorescence is blue, with over 95% of stones that fluoresce, showcasing this color. Note that there are diamonds that can fluoresce other colors like green or yellow, but these are pretty rare.
Fluorescence is caused by the presence of certain trace elements within the diamond’s crystal structure during formation, like boron and nitrogen, which incidentally are also responsible for a diamond’s color. Fluorescence is a completely natural occurrence, and around 25% to 35% of diamonds exhibit some level of it.
The Gemological Institute of America’s diamond grading reports include fluorescence grades. This grade reflects how noticeable the fluorescence is under UV light: none, faint, medium, strong, very strong. Keep in mind that fluorescence doesn’t always translate into a visual difference in normal lighting conditions.
Does Fluorescence Affect How a Diamond Looks?
For most diamonds, fluorescence wouldn’t have any noticeable effects on how a stone looks in day-to-day scenarios.
Under normal lighting, most people can’t tell the difference between diamonds with fluorescence and those without.
That said, there are nuances and exceptions to this.
There is a school of thought that believes that in lower-color diamonds (like those in the G to J range) blue fluorescence can make the stone appear whiter by offsetting warm or yellow hues.
In this way, fluorescence may actually enhance a diamond’s appearance.
Contrary to this, in diamonds with higher color grades that are visually colorless(D to F), some believe that strong fluorescence can cause a diamond to look hazy or milky, given the fluorescence light being shown on a clear background.
While this gets mentioned often, it’s worth noting that a GIA study found this effect in just 0.2% of fluorescent diamonds, making it super rare.
At the end of the day though, perception is personal.
What one person sees, another might not even notice. That’s why viewing diamonds in person is always a good idea.
A reputable jeweler can help you see whether fluorescence makes a difference for your eye, or not at all.
Does Fluorescence Affect Value?
Fluorescence can impact price, but not always in the way people expect.
Because of the preference for ice white stones, there is a bias for no fluorescence in the market.
This causes diamonds with strong or very strong fluorescence to sometimes be priced slightly lower than those without it—even if there’s no visible difference in beauty.
For those in the know, this creates an opportunity: a diamond with medium to strong fluorescence may look just as brilliant, and even appear whiter in lower color grades, while offering better overall value.
Final Thoughts
Fluorescence isn’t necessarily something to avoid, or something to look for - it’s just another thing to consider when selecting the right diamond.
In many cases, it makes no visible difference at all.
In others, it might offer a slight visual benefit or a more attractive price point.
Given that a diamond is both an emotional and a monetary investment, you owe it to yourself to be informed prior to making a decision.
That being said, when it comes to diamonds, there are definitely other factors out there that will have a much greater impact on the way a stone looks, like its cut or color.
With this in mind, the best way to choose the right diamond is to see it in person with guidance from a knowledgeable jeweler.
That’s where we can help.
At SUNSHINE, our GIA-certified gemologist and experienced team are here to guide you along in your diamond jewelry to help you explore your options with confidence.
Whether you’re choosing a center stone for your engagement ring or comparing diamonds for a custom piece, we’ll walk you through everything—fluorescence included.
