Understanding Diamond Fluorescence: What You Need to Know

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Picture this: You’re in a jewelry store, admiring a stunning diamond, but as you scrutinize it under different lighting, you notice a distinct glow. Could this be diamond fluorescence? Join me as I explore the fascinating phenomenon of diamond fluorescence and its significance on your engagement ring.

People don’t like to talk about fluorescence because it can be complicated, but it is important that you understand it.

Fluorescence sometimes makes diamonds look hazy or milky in sunlight or under fluorescent lighting.

Approximately 25-35% of all diamonds exhibit some type of fluorescence.

The vast majority of diamonds that are fluorescent have a visible shade of blue.

When is diamond fluorescence a good thing?

Fluorescence refers to the strength or intensity of a diamond’s reaction with ultraviolet light.

When you look at a GIA or AGS diamond certificate you will see fluorescence noted as none, faint, medium, strong, or very strong.

In certain color grades, fluorescence can be a good thing.

With diamonds of a lower color, fluorescence may make a diamond appear to be whiter than it actually is.

For example, a J color diamond with medium fluorescence will actually make the diamond look more appealing. The actual color is a J. The whiter look is a bonus.

All this may be confusing. Here are some easy to understand guidelines.

D,E,F,G color

The most desirable florence is none or faint. Don not consider fluorescence grades of medium, strong, and very strong.

H,I,J,K color

The most desirable fluorescence is none, faint, or medium. The medium intensity will actually make your diamond appear slightly whiter. Do not consider fluorescence grades of strong or very strong.

Please note that I am advising you to stay away from strong and very strong levels of fluorescence. This is because intense levels of fluorescence will make a diamond appear slightly to severely hazy or milly when in the sun or under fluorescent lighting.