Question for anyone good w. UV lights & fluorescence.

[beaujolais]

Question for anyone good w. UV lights & fluorescence.

I've been wanting a very fluorescent stone for a long time. I just bought a small one, supposedly with great fluorescence. Seller sent me a UV picture - nice bright blue.

However, I got it and to my UV light - it just lights up with a whitish color (in the dark). My UV light is a 380 nM, sellers is a 365 nM. Seller says the shorter wavelength of his UV light shows the fluoro better and that is why. Does this sound right?

Also, an anyone recommend, a not too expensive, UV light that will do the right job for me?

Thanks so much, Sonoma

 

[whatmeworry]

Hi Sonoma, not sure I have much to add except to say that my diamonds fluoresce white blue just fine with a 385 nm keychain led. Are you saying that at 385 nm you are getting a strong white fluorescence that looks nothing like the picture that you got?

 

[beaujolais]

-- you are getting a strong white fluorescence that looks nothing like the picture that you got? --

Yes. The photo has a strong blue fluoro, in person it has a white fluoro.
? ? ?

Thanks.

 

[Karl_K]

That is interesting.
Does it go blue in sunlight?

The wavelength of the UV does make a difference in how a diamond reacts.
The low cost uv leds are near UV just barely into the UV range where the gemology uv tube lights are further into the UV range.
The further into the uv range the more potential for eye damage so shorter wave length uv leds are harder to come by, they are also harder and more costly to produce.

 

[beaujolais]

Ah, Storm . . . First, I hope you are feeling o.k. Then, I am sending good wishes for your first holidays as Mr. & Mrs.

No, it doesn't go blue outside. Fortunately, it is a tiny thing so no need to worry about returning. I also got one that shows strong orange fluoro and that is Kewl.

Thanks so much. I need to research more. I want to understand this topic better. I was just looking on Rio & Kassoy and all and their UV lights are 380 nM (nanometers), same as mine. I do believe there is some link to 365 nM and seeing good fluoro but I've not figured it out yet.

I'm hoping Dave, John or Garry will see this as they are well versed in fluoro.

Thanks so much & Happy Holidays to you and the Mrs.,
Sonoma

 

[beaujolais]

.

 

[whatmeworry]

The seller could be right in that a 380 nm UV could still emit a lot of visible light into the stone (where the reflections would overwhelm the flourescence), whereas a 365 nm would have more UV and less visible light. Try it with the diamond on a black non-reflecting surface and the UV light source set a bit away from the diamond. Still, if you're getting orange fluoro on other stones it doesn't sound like your UV source has a lot of bleedover into the visible range.

 

[Garry H (Cut Nut)]

All the advice so far is good.
Here are some solution options:
1. get a whole range of different UV frequency LED's

- there is an article linked here on Pricescope on a gemeology site somewhere that explains all of this in great detail. Does anyone remember it?

2. Send your LED to the vendor and ask him to get you samples that work with that frequency.
3. Take you diamond to gadget stores and find an LEd that works well.

 

[beaujolais]

Thanks soo much What Me & Garry. Will do.

I felt guilty for putting this back to the top again, but I'm glad I did.

Appreciate it !

Happy Holidays,
sonoma