Can UV Light Damage Diamonds?

Can UV light damage diamonds?

Diamonds are popular for two main reasons. Their sparkly beauty and unbeatable toughness of 10 Moh on the hardness scale. And yet, diamonds are not invincible. Can UV light damage diamonds? Let us see what happens when diamonds are exposed to UV light for too long.

The manner in which diamonds are formed helps determine their identity. Diamonds are formed under extremely high pressure and temperature that exists within a specific depth under the earth. Many conditions have to come together to form the rare diamond. Special chemical combinations give them the exceptional characteristics that would otherwise make them just another mineral.

Can UV light damage diamonds: What is fluorescence?

There are many ways in which a diamond is graded; by its cut, clarity, carat, and color. They also have an additional characteristic which is fluorescence. Diamond fluorescence is actually the effect that UV light has on diamonds. Fluorescence is the visible light that some diamonds emit when exposed to black light or UV rays.
By definition, fluorescence is the reaction of a diamond when exposed to long Ultra Violet Rays. UV rays are one of the main components of sunlight. So when a diamond is exposed to the sun, the diamond emits fluorescence.

Now that you have understood what fluorescence is, let us see if fluorescence is bad for diamonds. An important fact to note is that not all diamonds show fluorescence. Only about 25-35% of diamonds would show this characteristic, and only 10% of them would show enough fluorescence to impact the diamond’s appearance. The color is visible in 95% of diamonds that show fluorescence is blue. Fluorescence can make yellow diamonds look colorless or white.

According to studies by the GIA, the intensity of fluorescence has no wide effect on appearance. And an average person will not be able to distinguish between a diamond with or without fluorescence.
Now coming back to the question, can UV light or fluorescence affect diamonds? The answer is no. Diamonds that have fluorescence have no structural difference from diamonds that have. Small differences in the structure of a diamond can either cause or prevent fluorescence, but that does not mean that exposure to UV light will change their composition in any way.

However, in the few diamonds that do have fluorescence, exposure to sunlight can cause them to change color. Depending on the amount of fluorescence, the diamonds will look blue in sunlight and will make them appear cloudy or milky. Exposing your diamond to strong sunlight is not recommended as it can degrade its color. When the amount of fluorescence is high in a diamond, the resulting chemical reactions can make it bluish, hazy or oily.

For this reason, diamonds with fluorescence are sold at a discounted rate of 5-25%. An average person would think nothing of the fluorescence and would also be happy to get much clearer-looking diamonds for a discounted rate, but to those who do notice, the diamond essentially has less value.

Can UV light damage diamonds: Conclusion

Can UV light damage diamonds? If you have no idea whether your diamond is fluorescent or not, you can take it to the jeweler to have it tested. In the meantime, it is always a good idea to avoid wearing diamonds under bright sunlight or put them in a UV-resistant setting. Or you can keep them protected with a UV-resistant coating. Always remember to store them away from direct sunlight.

On the other hand, these changes are very minimal, if even non-existent, because only less than 35% of diamonds have fluorescence. UV will not affect the structure of diamonds in any way. And overall, it is not much of an issue to stress about. Diamonds are still very valuable, fluorescence or not.


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