You will find fluorescence in following grading: 
NIL or NONE, Faint, Slight, Medium, Strong, Very Strong.
The fluorescence can be Blue or Yellow.

D - E - F colors with Strong Blue fluorescence are exceptional and therefore extremely rare, 
accentuating the brightness. Called Blue-White diamonds.

When white diamonds in D to F color are Blue fluorescent it quotes the color to the highest grade BLUE WHITE.

Warmer white colors from G to Z with Blue fluorescence will enhance the Color to white
and will look closer to colorless White. A very positive fact.

Very strong fluorescence can influence the clarity when it turns milky. You will see by naked eye that the diamond turns milky. It is always clearly indicated on the GIA, HRD and IGI certificate.

Blue-White Diamonds
The mysterious Blue-White Diamonds, Registered Brand Name, explained

Blue-White, Strong blue fluorescence: do influence the diamond color to the highest fashion color   
and it will enhance the appearance of a diamond.

Diamond dealers used the term "Blue-White" to refer to colorless Exceptional White D - E and Rare White + F - EX EX EX H&A ideal cut diamonds with rare strong blue fluorescence.

This is the signature of ultimate visible high class fashion!

The term actually became a status symbol amongst the public and to this day Experts will ask for a Blue-White diamond
the rarest color.

Rule 28 of the US Federal Trade Commission's Trade Practice Rules for the Jewelry Industry addresses this issue:

Rule 28 Misuse of the term "Blue White": 
"It is an unfair trade practice to use the term "blue-white," or any other term, expression, or representation of similar import, as descriptive of any diamond which under normal, north daylight or its equivalent, shows any color or any trace of any color other than blue or bluish." 

In other words
only a diamond with Strong BLUE fluorescence can be represented as Blue-White Diamonds.
A real collectors item, probably Yours 

Email me for a quotation of a very rare Blue-White Diamond
 Email     Tel: +32 3 233 29 90 
Antwerp World Diamond Center, Diamond Exchange, Hoveniersstraat 2, Antwerp / Belgium / Europe
This page was last updated on: October 19, 2017
​Copyright Ajediam All rights reserved
What is good and bad fluorescence? 
Learn about the influence on color and brightness and find out how GIA grades by its intensity. 

Fluorescence simply explained: 

The difference in energy between the absorbed light and emitted light is called fluorescence.
By no fluorescence is the absorbed light equal to emitted light, Neutral. On certifcates it is described as NONE
If the emitted light is stronger than the absorbed light the diamond is called fluorescent.

What is Blue White?
Know all about the registered very rare Blue-White Diamonds
analysis of your needs