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Diamonds That Glow Under a Black Light

Have you ever went bowling during Rockin’ Bowl where they played fun music and had black lights on the lanes? Did your diamond ring emit a bluish, ethereal glow? What you witnessed is called fluorescence!

Simply put, fluorescence is the bluish light emitted by a diamond when exposed to ultraviolet light. The most common color is a bluish glow, although, in rare cases, a yellow or orange light can occur, but only about 25% to 35% of diamonds will actually fluoresce.  The Gemological Institute of America’s diamond grading reports grade the intensity of the fluorescence as None, Faint, Medium, Strong, or Very Strong. 

So, is Fluorescence good or bad?? Well, that is up to you! Sunlight does contain ultraviolet light, so it is possible to see fluorescence in a diamond, but most people don’t consciously see fluorescence in sunlight. Interestingly, I have seen diamonds that had a lower color grade but had fluorescence, and it helped the diamond face up with a whiter look!  As far as price goes, generally, fluorescence is seen as a defect and will bring your diamond price down a little. If you can’t see the fluorescence (except under a blacklight) and/or it helps make your diamond shine brighter, AND the price is lower, I think that is a great thing!  

But again, it is up to you! I always advocate for seeing your diamond in person before buying it because you have the opportunity to see the things that bother you or don’t bother you. If you saw fluorescence in a diamond and you didn’t like it, then you can pick another!

There are many details to consider when buying a diamond, and I would love to help you! Angela Cisneros Jewelry Concierge brings back the joy and confidence of jewelry shopping, so that you can celebrate with ease! My by-appointment approach means:

  • One-on-one appointments (personal attention and no crowds!)

  • Discretion and privacy (surprises remain surprises!)

  • Expert help from a Graduate Gemologist with 26 years of experience (yep, that’s me!)

Learn more about me and my process: 

Book your FREE appointment with me today! 

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