Baltimore (410) 837-0290
Washington, D.C./Chevy Chase (301) 718-4825
Northern Virginia (703) 714-9553
Go Back
Diamonds

What is Fluorescence in Diamonds and Why Does it Matter?

Jul 16, 2020

Have you ever noticed how sometimes, a diamond’s sparkle can take on a blueish glow? That’s due to something called fluorescence. While we focus on the color of a diamond (or lack thereof) to grade the diamond’s color, there’s another factor that can come into play when assessing a diamond’s natural brilliance – and that’s fluorescence. While all diamonds have natural color, only 25-35% of diamonds exhibit some degree of fluorescence.

We use fluorescent lamps for a more controlled setting to see the intensity of fluorescence in a diamond, though it is possible to see a diamond’s fluorescence under natural conditions. If you think of ultra-violet lights, they make your whites look whiter and blacklight posters glow. The same is true of diamonds in ultra-violet light, which is how we determine whether a diamond has fluorescence. The most common color to see under fluorescent conditions is blue, but diamonds can fluoresce with an orange or yellow light.

So why does diamond fluorescence matter?

It comes back to that natural brilliance and color. Diamonds with a blue fluorescence and a lower color grade (or higher presence of color) may appear more colorless in settings with UV light – such as natural daylight. This can help a diamond with a medium to strong bluish fluorescence command a slightly higher price per carat than similar diamonds that do not fluoresce. The opposite is true for diamonds with higher color grades. Because they already have so little color naturally, a higher fluorescence can cause the diamond to look hazy or oily. This would mean a diamond with a higher color grade might command less per carat due to its fluorescence.

Because diamond fluorescence can be so variable, and occurs in a fraction of the overall number of diamonds, there’s no official grading scale used. Instead, a certified gemology report might include the level of intensity observed in a diamond’s fluorescence – if it is there at all. The reason for that comes back to how the diamond’s color and transparency is altered by fluorescence.

The good news is, the average person can’t tell the difference between diamonds that do or don’t fluoresce. After all, one needs to be in the right conditions to see a diamond’s fluorescence – so bright sunlight, a tanning bed, a dance club where blacklight is used, etc. Once the light source is removed, the diamond will stop fluorescing.

Something to keep in mind though is that the brilliance of a diamond has more to do with how it is cut than how it fluoresces. Certain cuts are designed to attract and reflect light, which is what creates that sparkle. And just like shopping for a diamond, beauty is in the eye of the beholder. Ultimately, it comes down to what makes you happy.

If you are considering a diamond with bluish fluorescence, take the time to look at it under different kinds of lighting, including natural daylight, and compare it to other diamonds of the same color. Our showroom has plenty of windows so you can review the diamond’s brilliance, cut, clarity, and yes, fluorescence firsthand. Start your diamond buying journey today by making an appointment or calling our Baltimore store at 410-403-3091!

Read The Latest News From Samuelson's

Engagement Ring Trends 2026

Apr 6, 2026

Engagement Ring Trends Shaping 2026 Engagement rings will always have a central role in jewelry. They’re more than fashion. They’re more than investments. They represent love and commitment, and that makes the choice of engagement rings incredibly…

Read More

Best Vintage Rolex Investment Guide

Mar 23, 2026

Which Vintage Rolex Is the Best Investment? Have you ever wondered if a Rolex is a good investment? You’re not alone – and yes, a quality Rolex watch can still make for an excellent asset well worth the investment. Vintage Rolex watches have…

Read More

How to Value a Vintage Rolex

Mar 9, 2026

How to Value a Vintage Rolex: A Collector’s Checklist There are few watches that carry the weight of a vintage Rolex. There are Submariners that have been passed down from father to son over generations. Or there’s that vintage Datejust that’s…

Read More

GIA vs AGS Diamond Certification Guide

Feb 23, 2026

Why Diamond Certification Matters: GIA vs AGS Explained When you’re investing thousands or more in an engagement ring, there is a single document that protects your purchase more than any other: the diamond certification.  We’ve helped numerous…

Read More

Stay In Touch

  • This field is for validation purposes and should be left unchanged.

Shopping Cart

Search