I have a diamond that GIA graded medium blue fluorescence.
I also have another diamond that GIA graded "none" fluorescence.
When I wear them side by side in the direct sunlight I see no difference.
I think the blue that I DO see must be reflections of the blue sky.
Hi
I have a medium blue fluorescent diamond I/SI2 .I can't see any difference in sunlight compared to my non fluorescent diamonds .
I think the diamond needs to be strong or very strong blue for the effect to appear .
I agree, I wore a diamond with med blue for over 20 years before a jeweler mentioned to me that it had it! I never noticed it anywhere! (Didn't go where there were black lights, apparently!)
Because there truly are no objective standards in use for measuring the amount of fluorescence equal to GIA MB, it is always unknown how any individual diamond will react. You can have stones which have no visible reaction in sunlight all the way to those which definitely cloud over or turn a bit of color in the blue, purple or yellow fluorescent reaction color range. In between reactions must also happen which the casual observer does not detect yet ones which a diamond dealer would clearly see something taking place. TO compaound the problem, some diamonds graded MB only actually have slight UV reactions and others graded MB have amazingly strong UV reactions. However the wind blew the day they were graded, so goes the UV grade often applied to an individual diamond.
The questions is a lot like the question about how eye-visible are inclusions in a particular diamond. It depends on your eyes, the eyes of the grader, how closely you look, how liberal the adviser, the definition used by the seller of what makes a diamond they sell "eye-clean". The best method is to see the stone, test it under conditions which assure you that this particular diamond is the one which is best for you to buy.
The image below- taken in natural lighting with a fair degree of UV shows ( on my monitor anyway) the blue tint I can see in real life.
the stone shown has strong blue- so a medium blue stone would likely show less than that
My OMB has MB fluor and I can actually see a blue tint in the sunlight.
My previous cushion also had MB fluor, and I never noticed any blue.
I'm not sure whether the blue in the OMB is really a reflection of the sky, and perhaps my first cushion didn't pick it up, but I do see some blue at times.
I wonder if there are any Youtube videos of MB stones in sunlight. It might be worth a look.
I have a med blue EC and i cant see any fluor in sunlight in fact ive had my ring for a couple of months now and ive yet to see its fluorescence at all!