Diamond Articles

What is Diamond Fluorescence

March 22, 2019 - Diamond Articles
There are a multitude of factors that affect a diamond’s quality and value. While you may have mastered the 4 C’s and can tell a princess cut diamond apart from a cushion cut diamond; have you heard of fluorescence? If you are asking yourself “what is diamond fluorescence?”, you are not alone. Fluorescence is one of the lesser understood diamond grades that has sparked many debates among those in the diamond industry. Keep reading as we explain just what diamond fluorescence is, the different types of fluorescence, how fluorescence affects a diamond and where you can find your diamond’s fluorescence.

Get the answers to the following questions:


What is diamond fluorescence?

So, just what is diamond fluorescence? Fluorescence refers to the soft blue glow that a diamond emits when exposed to ultraviolet light, such as a black light. This blue glow is only temporary and stops once the ultraviolet light is gone. While blue fluorescence is the most common, on rare occasions the soft glow can be yellow, green, red, orange and white.

what is diamond fluorescenceFluorescence is caused by trace elements in the diamond and, according to the Gemological Institute of America, about 25% to 30% of diamonds exhibit a degree of fluorescence. Of all of the diamonds that possess fluorescence, the GIA states that only about 10% of these stones have fluorescence can affect the diamond’s appearance. In most cases, people are not able to detect fluorescence with the naked eye.


Types of diamond fluorescence

Now that you know what diamond fluorescence is, let’s cover the degrees of fluorescence. The GIA has detailed five degrees of diamond fluorescence:

  • None:No fluorescence nor influence on the diamond’s color.
  • Faint: Weak fluorescence and not a significant influence on the diamond’s color.
  • Medium: Moderate fluorescence, could influence the diamond’s color.
  • Strong: Significant fluorescence with a great influence on the diamond’s color.
  • Very Strong: Extreme fluorescence and a substantial influence on the diamond’s color.

Remember, the GIA stated that only 10% of all diamonds that exhibit fluorescence will be visibly affected in non-UV settings. Therefore, of that 10% only a small amount of diamonds (those with a high degree of fluorescence) will be visibly affected by fluorescence.


How does fluorescence affect a diamond?

The main way that fluorescence affects a diamond is by creating a cloudy, milky appearance and affecting the diamond’s value. The cloudy appearance is only noticeable in medium to very strong fluorescence. But how does fluorescence affect value?

what is diamond fluorescenceTo understand how fluorescence affects a diamond’s value, we need to understand diamond color grades. Color is one of the 4 C’s of diamond grading and details the amount of color, or lack thereof, that a diamond displays. This is graded on a scale from D, for colorless, to Z, for faint yellow. Strong blue fluorescence creates the appearance of a whiter stone than it’s color grade. This happens because blue is a complement color to yellow, creating the whiter appearance.

How fluorescence affects diamond value:

  • For high color grades (D/E/F) with strong fluorescence, despite creating a whiter appearance, fluorescence will lower the stone’s price by up to 25%.
  • For lower color grades, fluorescence has a much smaller, sometimes even negligible impact. In fact, some jewelers will sell diamonds with low color grades and notable fluorescence at premium prices as they look whiter. However, while the stone may look like a better color grade, they are not worth a premium as fluorescence does not add value.
  • For colored diamonds, fluorescence can be a very big issue. Colored diamonds can be extremely rare and valuable depending on the intensity of the color of the stone. However fluorescence will weaken the color and therefore have a very negative impact on price.


Where to find my diamond’s fluorescence?

If you have a certificate from a reputable diamond grading lab such as the GIA, you can reference this document to find your diamond’s exact fluorescence. If you have a jeweler’s appraisal for your diamond that includes fluorescence, take their grading with a grain of salt.

In reputable labs, expert gemologists assess a diamond’s fluorescence in a highly controlled environment with UV spectrum lights and a master set of fluorescent diamonds to best determine a diamond’s grade. Reports from jewelers can be subjective as they depend on the  specific jeweler’s skill, environment and tools.


How to upgrade my diamond

After our deep dive into understanding diamond fluorescence, you might be considering upgrading your diamond. At WP Diamonds, we are expert diamond, designer jewelry and luxury watch buyers who can help you sell the pieces you no longer love and become a step closer towards owning your perfect diamond.

With WP Diamonds, selling your diamonds, designer jewelry and luxury watches is so easy and fast that you can receive payment in as little as 24 hours after completing our online form. Thanks to our and rich understanding of the secondhand luxury market as well as expert gemologists and horologists, we will always provide you with competitive and honest offers. Customers love our simple and professional service because of our A+ rating with the BBB, hundreds of excellent reviews and 100% trust guarantee.

To begin selling your diamonds, designer jewelry and luxury watches with WP Diamonds, all you need to do is complete our simple online form with information about your pieces. Our team will then get back to you with a price quote. If you like your initial quote and want to get a firm buying offer, you can either schedule an appointment at one of our offices or request a free, secure, fully insured and overnight shipping label to our New York, UK or Hong Kong offices. Once our experts assess your pieces in person, we will contact you with a firm price.

You can accept payment by wire, check or cash (in-person appointments only). With our upgrade program, we can offer an additional 10% more in the form of store credit with one of our partners. We never employ any high-pressure sales tactics and you can always request to have your items returned to you through the same free, fast and safe mailing service.

Click the button below to see just how much you can get paid for your diamonds, designer jewelry and luxury watches today.


Bio: Written by one of our diamond, designer jewelry or luxury watch experts. With over 150 years of combined experience, our experts are able to comment on trends, share industry knowledge and provide diamond, designer jewelry and luxury watch education.

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