“For some higher-color stones, fluorescence gives the stone a milky white appearance , which greatly lowers value.
(International trade magazine Rappaport)

To understand this, we first have to understand what is fluorescence and how it effects the quality of diamond.

Fluorescence is the property of diamond , which makes it glow when it is kept under a UV ( Ultra Violet ) light. Fluorescence in a diamond is judged based on the intensity of the glow when it is kept under a UV light.

The grades for Fluorescence starts with None, which means no Fluorescence and as the intensity of Fluorescence increases the grades change from Very slight to Very Strong.

Fluorescence in a diamond is considered an undesirable property. Only None Fluorescence in a diamond is considered desirable, even the slightest hint of fluorescence lowers the quality of a diamond. When you decide to buy a diamond that has a higher color such as D E F (COLORLESS), you should also make sure that the diamond you chose has flurorescence grade of “ NONE”.
Generally, the higher the quality and price per Carat, the more fluorscence lowers value. (International trade magazine Rappaport)

We at ML Colourless Diamond, chose our diamonds with utmost care and precision. We check each and every diamond, personally, both before and after mounting to make sure that they meet the highest international standards.

When you decide to buy non fluorescent diamonds, you are gifting the rarest diamonds, which is not tinted by any impurity, just like your love, where you do not accept any thing else to dilute your love for your loved ones.