Posted on April 6, 2016 by

Diamond Fluorescence Isn’t the Evil Monster You Think It Is


One of the hotly debated topics in the diamond world is the issue of fluorescence in diamonds. Consumers are more often than not made to understand, thanks to jewelry merchants, that the presence of fluorescence in a diamond is a big no-no. But is diamond fluorescence really as bad as everyone thinks? Today’s blog offers up evidence to help debunk the widely held belief that fluorescence is to be avoided at all costs. Instead, we’ll discuss why diamond fluorescence isn’t the evil monster you think it is.





GIA Diamond Fluorescence Scale

The above diagram is GIA’s demonstration of five different diamonds with varying degrees of fluorescence, from none to very strong (top – exposed to UV light; bottom – in normal lighting conditions). Photo:


Why Diamond Fluorescence Isn’t Evil


Fluorescence is the result of diamonds exposed to ultraviolet (UV) light. It’s the visible light that a diamond radiates in the presence of UV light. GIA assesses fluorescence on the basis of the strength of the diamond’s reaction to long-wave UV light, a common element of daylight. A particular diamond with fluorescence will fluoresce for the entire time it is subjected to UV light. Common types of UV light include the previously mentioned daylight and black light in night clubs.


Five loose fancy colored diamonds of varying diamond fluorescence colors.

These are six colored diamonds selected from Diamond Envy’s inventory to illustrate the range of possible diamond fluorescence colors when exposed to a UV light source. From left to right: Strong Blue; Strong Green; Strong Yellow; Strong Orange; Strong White; and None.


Approximately one-third of diamonds contain fluorescence. In diamonds that fluoresce, more than 95 percent show blue fluorescence. Blue fluorescence is often a boon to yellowish white diamonds (i.e., colorless diamonds with lower color grades) as the blue fluorescence will make the yellow-tinted diamond appear whiter. On rare occasions, diamonds can also fluoresce yellow, white and even orange or green.


While fluorescence can have favorable effects on the apparent color of lower grade white diamonds, the presence of fluorescence can also prove to be detrimental to the appearance of diamonds in rare instances. Although it is not notably common, diamonds with extremely strong fluorescence can result in stones that appear hazy, milky or oily. However, this tends to be more the exception than the rule.


If you’re concerned that fluorescent diamonds are structurally compromised by the stones’ fluorescent property, rest assured that fluorescence has no effect whatsoever on the diamonds’ structural integrity. A fluorescent diamond is as structurally sound as one that has no fluorescence.


Colored diamonds from Diamond Envy inventory when seen in normal lighting

This is the same set of colored diamonds as above when viewed in normal lighting.


In normal indoor lighting conditions, diamonds that have fluorescence usually cannot be distinguished from non-fluorescent diamonds to the naked eye. But because of the established negative associations that fluorescent diamonds carry, such diamonds are not uncommonly sold at a pretty sizeable discount. So fluorescence can certainly work in a customer’s favor if you’re looking to save some money and you have nothing (inexplicably) personal against diamond fluorescence. As explained here, there is nothing inherently bad about fluorescent properties in diamonds. If you’re at all concerned that fluorescence can have an adverse effect on the appearance of a particular diamond, of course it’s always best to check out the diamond in person and see for yourself. As a general rule, it’s primarily the cut of a diamond that has the biggest impact on the brilliance and general appearance of a diamond and not usually fluorescence. In fact, the presence of fluorescence can be considered pretty unique as it adds an extra element to your diamond that non-fluorescent diamonds lack. Diamonds without fluorescence can’t exactly boast of the ability to glow different colors in black light, can they?



Searching for a colored diamond that possesses (or doesn’t possess) fluorescence? Shop our extensive loose colored diamond inventory!

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