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Understanding Diamond Fluorescence Let’s take a look at what diamond fluorescence is, how it’s graded, how it affects a diamond’s quality and what you need to keep in mind when considering diamond fluorescence as a whole.

What is Diamond Fluorescence?

Diamond fluorescence is the measurement of how a diamond visibly emits light when exposed to ultraviolet light. Examples of ultraviolet light (UV light) include blacklight and direct sunlight. It is estimated that around 30% of all diamonds have some kind of glow. When we examine the fluorescence of diamonds under UV light, the light that is produced is blue in colour in almost every instance. Very rarely do we note fluorescence of white, green, yellow or red.

According to GIA’s guidelines, fluorescence is graded into the following categories:

  • None
  • Faint
  • Medium
  • Strong
  • Very Strong

How does Fluorescence Affect my Diamond?

The grade of fluorescence found in a diamond will affect different diamonds in different ways. In some cases, fluorescence will improve the colour of the diamond, while in other instances fluorescence will make the diamond appear hazy or cloudy. When a diamond has a hazy appearance, its overall quality is impacted and will often result in less sparkle & a reduced aesthetic appeal.

When is diamonds with fluorescence a Bad Thing?

  • Strong or Very Strong blue fluorescence: Diamonds with a strong or very strong fluorescence grading will typically appear hazy and unclear.While this effect can usually only be seen in UV conditions, it is important to note that sometimes fluorescence can present itself in regular lighting conditions so it’s always better to be safe rather than sorry.
  • Medium blue fluorescence with a high color grade: Diamonds in this category will typically also appear hazy with a milky effect on the color.
  • Colorless diamonds and fluorescence: Diamonds in the D to F range are negatively impacted by fluorescence in many ways. On top of having a decreased clarity quality, their overall aesthetic appeal is decreased which means it will lose a significant amount of retail value.

Strong Blu Fluorescence It just makes sense that a diamond with strong blue fluorescence will only really impact those who spend their time under UV lights, seeing as fluorescence cannot really be seen with the human eye. Some people will claim that diamonds that display a strong blue fluorescence under UV lights will have a diminished appearance in regular lighting conditions too. This GIA study disproves this claim, but not indefinitely. To reiterate, fluorescence in a diamond refers to how the diamond emits light when exposed to UV light and when a blue color is displayed.

Keep the Following in Mind when Shopping for Fluorescent Diamonds

  1. If you have investigated diamonds with a high level of fluorescence and have determined that it doesn’t affect your personal taste, go ahead and purchase one.
  2. Remember that fluorescence can enhance a diamond’s color.
  3. Diamonds of a high fluorescence level, such as strong blue, won’t always have a diminished overall appearance.
  4. Because fluorescence is sometimes perceived as a negative thing, diamonds that feature fluorescence will cost less. Low levels of fluorescence can even sparkle more because of this.
  5. Make sure that the retailer you plan on purchasing your fluorescent diamond from has a decent return policy—you never know.
  6. As is the case with buying any quality of diamond, always purchase fluorescent diamonds from a reputable jeweler known for a high level of quality and service.
  7. While you are looking at fluorescent diamonds, don’t be shy to ask the jeweler to whip out their UV light. It’s important that you see, and judge, for yourself the level of fluorescence present & how that effects the diamond’s overall appearance.

High Fluorescence And Hazy Diamonds?

The answer to this one is highly dependent on the diamond itself. Some will claim that fluorescence cannot be detected by the naked eye while others will swear that they can tell the difference between diamonds that possess a high level of fluorescence compared to a low level at a glance. When you closely inspect diamonds, you may be able to see the difference between diamonds that have a strong fluorescence and diamonds that don’t. Under UV inspection, it will be noted that diamonds of a higher fluorescence grade can appear hazy, cloudy or even oily. What is important to remember is that diamonds with an extremely high level of fluorescence that can be easily identified by the naked eye are not commonplace and won’t often be a problem you need to deal with.

Fluorescence and Enhanced Color?

A fact that cannot be disputed is that in specific circumstances fluorescence will improve the color and overall aesthetic appeal of a diamond. A medium blue fluorescence is recommended for diamonds of the colors H and lower, and it is advised to avoid diamonds with strong blue fluorescence—especially in low colors as they are at risk of looking milky, filmy and hazy. The lower the color grade, the lower the chance of the diamond appearing milky. For example, H, I and J diamonds will appear whiter when a higher fluorescence level is present. Diamonds that have a yellow or brown tint will benefit from fluorescence as they will appear whiter and will appear to be of a higher quality than what it actually is. If you are nervous or skeptical, rather stay on the other side of medium blue. Remember, fluorescence can be a good thing. Sometimes, a diamond with fluorescence will be shinier and more sparkly than one that has no fluorescence.

Take a Minute Before Purchasing a Fluorescent Diamond

It can be considered risky to purchase diamonds with a high color that contain fluorescence. This is simply because there has been the odd instance where medium blue fluorescence diamonds feature a milky, hazy appearance in diamonds of higher colors (such as Gs or better). If you plan on purchasing your diamond in person, request a diamond with a strong blue fluorescence so you can see for yourself how fluorescence effects the overall appearance. If you know what kind of diamond you’ll be looking at, feel free to get hold of us should you have any reservations or if you’re in need of any information. Not only will the rock be more affordable but you will also be able to scope out any effects for yourself. Ask that the diamond be exhibited in different lighting conditions so you can make sure you are happy with it.

Do You Want to Purchase a Fluorescent Diamond?

There’s no denying that diamonds featuring a higher level of fluorescence are cheaper than diamonds that possess a low level, which makes it an appealing product to those of us who tend to focus a great deal on our budget. It’s advised that you shop locally for fluorescent diamonds, purely because you can see the diamond in person and gauge its reflective properties.

Keep in mind:

Always remember that a safe bet for a fluorescent diamond is an H, I or J diamond. They will benefit from a medium blue grading due to the fluorescence making the diamond appear whiter in color. Diamonds that are G or higher in color can benefit from no to faint fluorescence. But overall, every diamond is unique which is why we love them, right? If you would like our advice on a specific diamond, don’t hesitate to reach out to us.

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