The Fluorescence of the diamond
It's surprising, but true, a diamond can be fluorescent under ultraviolet light. When you know this characteristic, you wonder if it's good or bad, if it changes anything about the diamond, its appearance or its price. You are in the right place to find out more.
What is diamond fluorescence?
The fluorescence of a diamond is a light effect that can be seen under ultraviolet light. But it can also be found in sunlight, in a nightclub (Fun fact: it's the same effect as when you wear a white t-shirt in a nightclub) or through fluorescent bulbs.
A LITTLE BIT OF CHEMISTRY AND PHYSICS:
As a reminder: the diamond is made up of carbon (C) but it can also be composed of nitrogen, boron and aluminum. These elements react to UV light. Under UV light, they absorb this energy and move to a higher energy state. The goal of an element is to be as stable as possible. However, we have seen that the 3 elements: nitrogen, boron and aluminum are in a so-called "excited" state under UV light. In order to return to a stable state, the elements must emit all the necessary energy. They do this by releasing photons or the light is perceived as fluorescent.
We can now understand that the fluorescence of the diamond is due to the 3 elements that are: aluminum, boron and nitrogen.
What color is the fluorescence of the diamond?
The fluorescence of the diamond can be of different colors. Most of the time, the color is blue. Indeed, 98% of all diamonds with fluorescence will be this color. But there are other colors like white, green, pink or yellow fluorescence. The color of the fluorescence depends on the physical composition of the internal atomic structure of the diamond.
What color is the fluorescence of the diamond?
As with everything, each diamond will have a different fluorescence. There are 5 levels of fluorescence: none, weak, medium, strong, and very strong.
An expert's eye can differentiate a more or less fluorescent diamond with regular lighting but for an untrained eye, UV light is essential to notice the fluorescence.
What are the levels of fluorescence?
THE PALE BLUE FLUORESCENCE (NONE/LOW):
For the none level, this means that there is no fluorescence in the diamond. As soon as there is a bit of fluorescence, it will be a low-level diamond. They are recognizable because they are never blurry. So if you take a diamond with no fluorescence or a diamond with low fluorescence, there will be no difference.
It is preferable to choose a diamond with a color G or higher (article on color here) if you take a diamond with low fluorescence or none in order to save money without losing the overall brilliance of the diamond.
AVERAGE BLUE FLUORESCENCE:
The diamonds of this level of fluorescence are usually not blurry. For this level, it is better to opt for HK colors. Indeed, as previously mentioned: fluorescence is most of the time blue. It should be known that blue complements yellow, so a yellowish diamond like HK with medium blue fluorescence will appear whiter.
THE STRONG/VERY STRONG FLUORESCENCE:
A strong or very strong fluorescence makes a diamond appear blurry, sometimes with a hazy or milky aspect. It is often preferable not to buy a diamond with such high fluorescence. Diamonds of color D to F are the most likely to appear blurry when combined with strong or very strong blue fluorescence.
Be careful, this does not mean that colors below the F shade cannot be blurry. On the contrary, with strong blue fluorescence, most diamonds are blurry.
Why does blue fluorescence sometimes have a bad reputation?
The fluorescence of a diamond can be bad for its appearance. Indeed, elle can lead to a cloudy appearance that no one looks for in a diamond. This cloudy appearance is translated by milky spots visible to the naked eye. The "too blue diamond" is the name that can be given to this category of diamond.
Because of their bad reputation, diamonds with blue fluorescence tend to be cheaper, but this reputation is unfounded. (Fun fact: a few decades ago, so-called "blue white" diamonds with blue fluorescence were sold at a high price. These diamonds were originally high-quality diamonds, but they were later used as "lower quality" diamonds by sellers.)
Since then, the "blue white" label of these diamonds is banned and they are the cause of their unfounded reputation.
What is the advantage of blue fluorescence diamonds?
As we have seen, the fluorescence of a diamond can make it blurry, but this aspect is not systematic. In the case where a diamond has fluorescence, but has no blurry effect, then there are only advantages. Because of its false bottom, a fluorescent diamond will have a lower price even if it is not blurry! (Fun fact: this diamond will be 10 to 15% cheaper compared to a diamond without blue fluorescence)
We must also not forget that the effect of a blue fluorescent diamond can make the diamond exceptional. In daylight, it is difficult to see its fluorescence, but if you expose it to UV light (like in a nightclub for example), the diamond will shine with an icy blue. Of course, this icy blue aspect must be tempered, but the surprise effect is guaranteed, everyone will remember the diamond that turned icy blue during a party!
Does fluorescence have an influence on the appearance of the diamond?
Yes and no to be honest. A study was conducted in 1997 by the GIA laboratory, they proved that "fluorescence had no overall effect on the appearance or transparency of color" but this same study also showed that diamonds with low fluorescence have a clearer tendency compared to diamonds with strong fluorescence.
Here we notice a doubt and a disagreement of experts on fluorescence. In fact, this study is more or less contradictory. It is better to know that fluorescence can make a diamond blurry while knowing that this is not systematic.
But then, is it a good thing to have a fluorescent diamond?
The fluorescence of a diamond is not a "major flaw", it should not deter you from buying a diamond. An icy blue effect can add a unique "soul" to your diamond. Be careful, you should ask your diamond dealer for advice if you want a fluorescent diamond in order to choose the color that will go perfectly with it. Moreover, the blurry aspect is not systematic and therefore does not necessarily occur. It's a matter of taste, you will either prefer a usual diamond or a diamond with a touch of blue fluorescence that will make your diamond incomparable.
1 ) Fluorescent diamonds are not as rare as that, except for diamonds with very strong fluorescence. But rarity is appealing, isn't it?
2 ) Fluorescence is marked on the diamond certificate
3 ) In the study conducted by the GIA, observers preferred diamonds with fluorescence that appeared whiter.
Advice from the diamond dealer:
Many may be hesitant when it comes to fluorescent diamonds. But this is not the most important factor. It's often a matter of taste.
- If you choose a diamond with strong fluorescence, do not choose a D to F color diamond: they will probably appear opaque.
- If you choose a diamond with medium fluorescence, you need a H to K color diamond: the combination of the blue color of the fluorescence and the yellow color will make the stone appear whiter. This will also save you money on the diamond's color and its fluorescence.
- Diamonds with too much fluorescence and therefore a milky and less transparent appearance should nevertheless be avoided.
- Finally, fluorescence is essentially a matter of taste. But who has never dreamed of having such a unique diamond, that when optimal conditions are met, it changes color? It's also a surprise effect at a lower cost that can always surprise.
