• Free delivery in US · Free resizing · Lifetime warranty

Diamond Fluorescence: What It Is and How It Affects Value

When shopping for a diamond, most people focus on the 4Cs—Cut, Color, Clarity, and Carat. But there’s another characteristic that can quietly influence both a diamond’s appearance and price: fluorescence.

In this blog, we’ll explore what fluorescence means in diamonds, how it’s graded, and whether it’s something to seek or avoid, depending on your goals.

What Is Diamond Fluorescence?

Diamond fluorescence refers to how a diamond reacts to ultraviolet (UV) light—typically by glowing blue. This natural reaction is caused by trace minerals in the diamond’s structure.Fluorescence is not visible under normal lighting but becomes apparent under UV light, such as direct sunlight or black light.
Want to learn how diamonds are formed? Check out our diamond education center.

Fluorescence Grading Scale

Fluorescence is graded on the following scale:

  • None – No glow under UV
  • Faint – Minimal glow
  • Medium – Noticeable blue glow
  • Strong – Clear blue glow, can affect appearance
  • Very Strong – Intense glow, may impact transparency

View our lab diamond fluorescence filter to compare diamonds by their glow.

How Fluorescence Affects Diamond Value

Colorless Diamonds (D–F Grades)

Strong fluorescence in D-F diamonds may create a hazy or oily look. These diamonds are often discounted by 10–15%, making them a smart choice if there’s no visible impact.

Near-Colorless to Faint Color Diamonds (G–J Grades)

Fluorescence usually has little effect here. Most diamonds in this range are unaffected in appearance or value.

Lower-Color Diamonds (K–M Grades)

In this range, blue fluorescence can help neutralize yellow undertones, making the diamond appear whiter. This can increase visual appeal and value—especially for budget-conscious buyers.

Explore K–M lab-grown diamonds with strong fluorescence.

Should You Buy a Diamond with Fluorescence?

Here’s a simple breakdown:

  • For value buyers: A D–F diamond with strong fluorescence might offer great savings.
  • For visual impact: Fluorescence can enhance lower-color diamonds beautifully.
  • For collectors: Some people love the black-light glow of very strong fluorescent stones.

Fluorescence is often misunderstood—but it can work in your favor. The key is knowing how it pairs with a diamond’s color grade and ensuring it doesn’t affect transparency.

At 1ctlabdiamonds.com, you can filter by fluorescence to find the perfect glow for your budget.

Looking for a diamond that glows just right?
– Shop lab-grown diamonds by fluorescence and find your perfect match today.

Need help choosing?
– Chat with a diamond expert or read more in our Lab Diamond Buying Guide.

Diamonds
Solitaire
Halo
three-stone
Pavé
rings

You need to know

Is Rare Carat Legit? The Price Difference Feels Wrong — Until You Understand This

When something expensive is priced significantly lower, hesitation is natural. That reaction is exactly what drives most searches asking “is Rare Carat legit?”. The diamonds look identical on paper, the certificates match, yet the price difference feels unsettling.. just enough to make people wonder whether they’re missing something important. If you’ve been engagement ring shopping for a while now, you’ve probably asked this question yourself: “Is Rare Carat legit… or is there a catch??” The doubt usually starts when you

Read More »
January 26, 2026 No Comments

Studs vs Bracelets vs Pendants: How to Choose the Most Personal Jewelry (2026 Decision Guide)

How to Choose Between Studs, Bracelets, and Pendants Based on Personal Meaning When someone searches “studs vs bracelets vs pendants”, they’re trying to answer something quieter in reality: “What kind of jewelry will feel most personal to me in everyday life?” They’re standing at a decision that feels vague but isn’t, because personal jewelry becomes part of your identity, routine, and memory. This 2026 decision guide helps you choose between studs, bracelets, and pendants based on how personal you want

Read More »
January 22, 2026 No Comments
Shopping Cart