Can you spot fluorescence in a yellowish stone without UV?

[AllAboardTheBlingTrain]

Just what it says on the tin!

I still haven’t gotten my ering on my finger but my SO is kindly allowing me to visit it once in a while so I don’t rip the place apart looking for it haha. The last time I had it on my hand I noticed that there was a little bit of blue look/flashes when I saw it in the sun. I tried to take a picture of it but I couldn’t really capture it.

The stone is a low alphabet colour and is uncerted so I have no way of verifying it, and it doesn’t matter to me either way, but I was wondering what that sort of blue light could be. Is it just normal rainbow flashes and I’m confusing it with fluoro? I don’t have any yellow diamonds or even yellowy diamonds so I’ve no way of comparing it to other stones.

I don’t have a UV tester, though I might buy one out of curiosity. Was just wondering what I should/could “expect”

 

[Karl_K]

Blue in sunlight could be a lot of different things of which fluorescence is one of them.
Sunlight has a lot of UV.

Now if it was flashes of blue it was more than likely something blue in the environment reflected in the diamond.
Blue sky, blue shirt, blue cap, blue car, blue wall and the blue list goes on :}
Second is as you said: rainbow flashes

Blue only seen in small parts and flashes on and off is far far far less likely to be from fluorescence.

 

[Karl_K]

Just to answer the question as stated: "Can you spot fluorescence in a yellowish stone without UV?"
The answer is no because without UV there is no fluorescence.

 

[AllAboardTheBlingTrain]

Thank you so much Karl! I was wearing a grey jacket which may have influenced the appearance of the stone. I expect I shall have to test it while wearing white and maybe also something like red! It’s really an amazingly sparkly stone and flashes so many colours it’s blinding. I seem to remember now thinking it looked almost green at one point but since I was out in a park it’s possible it was reflecting the grass and the trees. It was brilliantly yellow at one point, then looked almost green and at one point kind of blue. The flashes are all colours, but predominantly yellow/blue/red/green in that order I think. Occasionally a big white flash but that only seems to happen indoors. I haven’t worn it long enough to gauge its personality since I only get my hands on it for a few minutes at a time!!

Perhaps I shall buy one of those cheap UV testers after all. I’ll wait until I have it in my hands for real though. Thanks for your answer

 

[Karl_K]

What cut is it?
Some cuts give you more of a tour of the environment around you than others.

 

[AllAboardTheBlingTrain]

What cut is it?
Some cuts give you more of a tour of the environment around you than others.

It’s a old transitional-ish round brilliant. It has the flowery pattern of an OEC in the middle and an open culet but also a flatter top than your average OEC and a consequently large spread. It’s an heirloom stone so there’s very little detail on it! The jeweler who made the ring estimated it as ST at the highest but that was not in a controlled environment or anything, I just asked his opinion. He did advise sending it to GIA but I decided against it because I don’t plan to sell it. I would think that GIA would probably give it a circular brilliant designation, but I don’t know if that definitively rules it out from being an OEC.

 

[Rockdiamond]

Hi !!!
The words "without UV"......that is a source of a lot of debate here....my position has always been that if there's enough light to ascertain a diamond's color, there's enough UV to stimulate the FL effects...whatever they might be.

Fluorescence affects each stone differently. This is especially noticeable in yellow, or light yellow diamonds.
There are stones that I can easily spot as fluorescent, in normal diamond grading lighting ( which doesn't have a high degree of UV)......generally this is not a good thing. In these detrimental cases, the stone lacks transparency- getting a "watery" look.
IN other cases, the fluorescence isn't visible, even in direct sunlight......
It's totally a case by case basis.

Having said all that- I agree with Karl- if you were seeing blue flashes- it was either fire or reflections.....

Congrats on the e-ring!!!

 

[Karl_K]

It’s a old transitional-ish round brilliant. It has the flowery pattern of an OEC in the middle and an open culet but also a flatter top than your average OEC and a consequently large spread. It’s an heirloom stone so there’s very little detail on it! The jeweler who made the ring estimated it as ST at the highest but that was not in a controlled environment or anything, I just asked his opinion. He did advise sending it to GIA but I decided against it because I don’t plan to sell it. I would think that GIA would probably give it a circular brilliant designation, but I don’t know if that definitively rules it out from being an OEC.

sounds awesome!
Will be waiting for pictures when you get it!

 

[AllAboardTheBlingTrain]

Hi !!!
The words "without UV"......that is a source of a lot of debate here....my position has always been that if there's enough light to ascertain a diamond's color, there's enough UV to stimulate the FL effects...whatever they might be.

Fluorescence affects each stone differently. This is especially noticeable in yellow, or light yellow diamonds.
There are stones that I can easily spot as fluorescent, in normal diamond grading lighting ( which doesn't have a high degree of UV)......generally this is not a good thing. In these detrimental cases, the stone lacks transparency- getting a "watery" look.
IN other cases, the fluorescence isn't visible, even in direct sunlight......
It's totally a case by case basis.

Having said all that- I agree with Karl- if you were seeing blue flashes- it was either fire or reflections.....

Congrats on the e-ring!!!

Thank you for the insight, David! I think I made a mistake in the title - I meant without a UV light, not “natural UV” or “lightbulb UV.”

I think the next time I get a hold of the ring I need to examine it a bit closer! I’ll wear white so I don’t influence the colour in any way and go check it out in sunlight again. I’ll try and get the blue and the green to show up again and see if it’s a flash or the stone turns a uniform-ish colour. The only stone I’ve seen with fluoro was a white diamond with SBF, but I think it’s easier to spot the “colour effects” of fluoro in a white diamond. Or more likely my stone doesn’t have fluoro and I’m driving myself nuts for no reason.

How do I know if what I see is fluoro and not a reflection? I assume if it’s a flash then I take it to be fire, but if it’s a colour across the stone? In normal room lighting the stone doesn’t look bluish, just varying intensity of yellow. I only spotted the blue/green outdoors. Also, does fluoro make a stone “glow” to the naked eye?

Thank you once again

sounds awesome!
Will be waiting for pictures when you get it!

Thank you Karl, for all your help as well! I actually had posted a pic of it a few weeks ago when it finally came in from the jeweler (the setting took ages). But I requested the mods to delete the thread after a few days for privacy reasons. Perhaps I will screw up the courage to post again will tag you if I do.