Learn the Lingo: Fluorescence - Gunderson's Jewelers

Learn the Lingo: Fluorescence


Shopping for a diamond can be a stressful undertaking, but the team at Gunderson’s are here to help make that process as easy as it can be—even fun! That’s why we’re committed to educating our clients on the lingo that they may encounter during their search for the perfect diamond. Gunderson’s is the leading authority on diamonds in the Midwest. and we’re excited to share that knowledge and passion with you!

Perhaps one of the most scientifically interesting aspects of diamonds is their ability to fluoresce. This results from ultraviolet light interacting with trace elements found in the crystalline structure of the diamond. What was a clear and sparkling gemstone can suddenly turn blue as it appears to glow in the dark.

Fluorescence is complicated, but it is not inherently bad or undesirable. Let this guide help you begin to understand how fluorescence works. Our team of professionals at Gunderson’s are here to educate you on finding the perfect diamond—whether it glows or not!

Fluorescence: What is It?

Simply put, fluorescence is the reaction of trace elements trapped inside a diamond with ultraviolet light (UV; black light). The UV light excites these trace elements, such as aluminum, boron, or nitrogen, and makes them glow a soft blue. Blue isn’t the only color a diamond can glow, but it is the most common. Some diamonds have been found to glow red, green, yellow, or white. As soon as you remove the diamond from the UV light, the fluorescence stops, and the diamond retains its normal clear and bright appearance.
fluorescence light on diamond
To make things more interesting, diamonds can actually glow after the UV light is removed. This ultra-rare phenomenon, known as phosphorescence, allows for a diamond to actually be charged by the UV light—allowing it to glow even after the black light is removed. Is this a bad thing? No, its science!  

Your diamond isn’t at any risk of being damaged if it glows under ultraviolet light—even if it phosphoresces. This is purely a scientific, natural characteristic of the individual diamond. Some are wary about purchasing a diamond that fluoresces; the diamond experts at Gunderson’s are here to help you explain the phenomenon and find the perfect gem for you.

Fluorescence: Why Should I Care?

Mainly, you should know that your diamond fluoresces so you’re not alarmed the first time you see your brand-new engagement ring glow under black light! Nothing can be more frightening than to think something is off on your new diamond ring! Not to worry—fluorescence is 100% natural and safe.

Actually, according to GIA (the Gemological Institute of America) almost 1/3rd of all diamonds possess the ability to fluoresce. Not only is it fairly common, but it also isn’t even noticeable by the majority of people when the diamond is not under UV light. Some diamonds show a slight milky or oily surface appearance when there is relatively strong fluorescence present, but most stones that fluoresce with mild to medium intensity do not have that issue.

If you work in an environment that is frequently under UV light, you may want to find a gemstone that doesn’t glow with fluorescence. In the end, it is your personal preference. Each diamond is unique in every way—let the experts at Gunderson’s help find the perfect one for you!

Learn the Lingo: Trust the Experts!

All of the loose diamonds that are hand-selected by the experts at Gunderson’s have been individually chosen for their beauty. Some fluoresce, some do not. As part of your shopping experience, your sales professional will guide you through the process of selecting the perfect diamond for you—fluorescence or not!