Spinels and fluorescence

[T L]

The LED UV keychain lights you can get on ebay for really cheap seem to be very harmless. That's what many of us "non-professionals" use to test UV fluor. I don't want to say they're completely harmless because I don't know 100% for sure, and I'm sure they vary from manufacturer to manufacturer. As always, when buying a UV light, read the manufacturer warnings.

I do not know of any other way to test fluorescence without a UV light.

 

[chrono]

There are 3 different UV wave ranges: long, medium UVB and short UVC. Long wave UV is fine and quite safe. It is advisable to wear some protective glasses and maybe even gloves when using medium and short wave UV light source even if not looking directly at it due to the way the waves radiate. As far as I know, the UV lamps are the only way to check for fluoro. The blacklights (disco lights) are safe as they only use long range UV.

 

[LD]

Date: 12/1/2009 7:12:30 AM
Author: Largosmom
No one has said if there is a safe way to use a UV light to test stones--or if there is another way to test fluorescence.

Laura

Short answer = yes!

As TL has said - buy an LED keychain or a blacklight torch. These are not harmful unless you put them up to your eye and stare into them for ages - and why you would do that leaves me a little perpexled!

Obviously you wouldn''t stare into a normal torch so why would you do it with these?

 

[Harriet]

klewis,

Long-wave UV should show off most fluorescent stones, so you can play safely. It''s loads of fun!

As for why one doesn''t hear the term "blue-white," that''s because the FTC has deemed it ambiguous and thus misleading.

 

[Largosmom]

So, to summarize...a low power UV light or black light (I actually have one which I used to identify some old "pet stains", should not cause harm as long as it is properly used for a short period of time...such as don''t point it in your eyes, and protect sensitive skin. Thanks! I''ll be checking my new purchases and have a reason to keep that silly light.

Laura

 

[colormyworld]

Do the research. Observe for your self and come to your own conclusions. Like I did.

 

[Gailey]

Date: 12/1/2009 8:49:12 PM
Author: colormyworld
Do the research. Observe for your self and come to your own conclusions. Like I did.

Well, I had never heard of that this might be a problem, so I did a quick google search of "hazards of black light exposure". Google lists 516,000 responses. I don''t know how much of a problem it is, especially in this context, but it seems to me that there is certainly enough information out there to justify Colourmyworld''s opinion.

I am grateful to Klewis for starting this thread and grateful to Colourmyworld for his suggestion. I have learned quite a bit. And whereas I don''t have to worry about black light exposure - cos I''m still not swayed by these glowing Mahenges!, I do perhaps need to take better care of my eyes when working outside and perhaps I ought to be concerned about the number of hours I stare at my laptop.

Knowledge is a wonderful thing and the internet allows us to find it, digest it and take away the bits that are important to each of us.

PR, with respect, I don''t think this was an appropriate venue for you to opine your views of Harriet in this manner. She and TL may well have differing opinions about aspects of gemology. They often express those differences to one another. I don''t think I have ever seen either of them use any of the rebukes on your list. As my Dad used to say to me when I was growing up, "You''re big enough, and ugly enough to fight your own battles".

 

[Harriet]

Platinum Rock,

Please distinguish between arguments ad hominem and statements of fact. I do not intentionally correct anyone on that which is subjective. As for the objective, I check the facts first. You have expressed an appreciation for legal and scientific research. I am an attorney by training.

 

[Stone Hunter]

Going back to the Fluor discussion...

I always abbreviate it Fluor. so I don''t have to remember how to spell the whole word -- bad speller that I am.

I found that a regular black light won''t show Fluor. You need a Fluor Black light. I haven''t been able to buy one locally.

Disney World uses alot of Fluor Black lights in their rides. So I think that that type of short term exposure is OK. Yeah I''m trusting in Disney having done the research. That said the rides don''t have you sitting in one spot staring into Fluro Black Lights.

I do enjoy wearing my gems to Disney.

I have learned from this thread that Sapphires Fluor. How cool. Thanks all.

 

[Harriet]

Stone Hunter,

Thanks for the levity.

Try www.kassoy.com, but please exercise caution when using the light.

 

[klewis]

Well I think we''ve covered it as far as UV light goes, but nobody took me up on the transmission luminescence question.

 

[Lovinggems]

Date: 12/2/2009 3:13:54 AM
Author: klewis
Well I think we''ve covered it as far as UV light goes, but nobody took me up on the transmission luminescence question.

I just bought RW''s book and I''m interested in this topic as well.

 

[chrono]

I’ve read something about this in a 1990 GIA report that only Tanzanian pink spinels have this characteristic. I have a pink Tanzanian spinel but have not checked for this.

 

[LD]

Date: 12/1/2009 10:24:41 PM
Author: Stone Hunter
Going back to the Fluor discussion...

I always abbreviate it Fluor. so I don''t have to remember how to spell the whole word -- bad speller that I am.

I found that a regular black light won''t show Fluor. You need a Fluor Black light. I haven''t been able to buy one locally.

Disney World uses alot of Fluor Black lights in their rides. So I think that that type of short term exposure is OK. Yeah I''m trusting in Disney having done the research. That said the rides don''t have you sitting in one spot staring into Fluro Black Lights.

I do enjoy wearing my gems to Disney.

I have learned from this thread that Sapphires Fluor. How cool. Thanks all.

Stone Hunter - they do! Look at the photo of my Mahenge Spinel. That was taken with a blacklight torch.

All - my husband is a lighting engineer. He has said that UV light CAN be harmful (even the UV lights used in discos but Low Wave UV light is highly unlikely to cause damage (especially the voltage/waves given off by the small torches) unless you shine it in your eyes and stare into it. If it wasn''t, trust me, there''s no way he''d let me use my little torches and getting this into perspective, would discos be allowed to use it if it were harmful?

 

[Stone Hunter]

Date: 12/2/2009 1:31:13 PM
Author: LovingDiamonds

Date: 12/1/2009 10:24:41 PM
Author: Stone Hunter
Going back to the Fluor discussion...

I always abbreviate it Fluor. so I don''t have to remember how to spell the whole word -- bad speller that I am.

I found that a regular black light won''t show Fluor. You need a Fluor Black light. I haven''t been able to buy one locally.

Disney World uses alot of Fluor Black lights in their rides. So I think that that type of short term exposure is OK. Yeah I''m trusting in Disney having done the research. That said the rides don''t have you sitting in one spot staring into Fluro Black Lights.

I do enjoy wearing my gems to Disney.

I have learned from this thread that Sapphires Fluor. How cool. Thanks all.

Stone Hunter - they do! Look at the photo of my Mahenge Spinel. That was taken with a blacklight torch.

All - my husband is a lighting engineer. He has said that UV light CAN be harmful (even the UV lights used in discos but Low Wave UV light is highly unlikely to cause damage (especially the voltage/waves given off by the small torches) unless you shine it in your eyes and stare into it. If it wasn''t, trust me, there''s no way he''d let me use my little torches and getting this into perspective, would discos be allowed to use it if it were harmful?

Well I bought a "black light" from Spensers but it''s just a regular light bulb with a black coating and it doesn''t make my stones show their Fluor. Your black light torch must be different.

Now that I''ve found out that Sapphires can have Fluro I need to check all of my stones. Maybe I''ll be pleasantly suprised!

I don''t know about Discos being allowed to use UV lights but I do trust Disney more than Discos. Which means that I need to either buy a "black light" online or take all my stones to Disney!

 

[Demon]

Date: 12/1/2009 10:24:41 PM
Author: Stone Hunter
Going back to the Fluor discussion...

I always abbreviate it Fluor. so I don''t have to remember how to spell the whole word -- bad speller that I am.

I found that a regular black light won''t show Fluor. You need a Fluor Black light. I haven''t been able to buy one locally.

Disney World uses alot of Fluor Black lights in their rides. So I think that that type of short term exposure is OK. Yeah I''m trusting in Disney having done the research. That said the rides don''t have you sitting in one spot staring into Fluro Black Lights.

I do enjoy wearing my gems to Disney.

I have learned from this thread that Sapphires Fluor. How cool. Thanks all.

Otto Frei has a loupe that has both led and uv lights, very reasonably priced.

 

[Demon]

Date: 11/28/2009 5:05:24 PM
Author: LovingDiamonds
Totally agree with TL. Fluorescence whilst clearly visible with UV light (to confirm it''s presence and just to go W

W!) also will have an affect on how the gemstone performs.

I''m going to show you a diamond. This is an I colour - which in normal circumstances you''d expect would be starting to show a warm colour. You wouldn''t say a normal I colour was white like an F for example. However, combine it with strong fluorescence and the blue of the fluor cancels out the yellow of the diamond so what you get is (in most cases) a gemstone that appears to be whiter than it''s actual grade.

So here''s the diamond. The first photo is in natural light inside - with light coming through the window. You can''t see any yellow. The second photo shows it in strong sunlight - can you see the blue tinge? That''s not a reflection. That''s the fluor.

Ok - so that''s how it affects my diamond. Now look at the pictures of my spinel. With the fluor it glows and the colour is super-enhanced in sunlight. In fact, this gem very rarely does anything other than glow. I''m sure that the fluor is the reason.

The other effect of fluor is that it can actually help gemstones to appear to change colour (or that they do change colour). I have a pear sapphire that I bought recently that changes from a blue/violet to a purple. It fluoresces red.

Hope that helps.

I''m glad to hear about your sapphire. I have one that in some lighting is sort of magenta, and can also look a dark grape in the shade. It fluoresces red too, and kind of freaked me out - I thought maybe it had been treated with something!

 

[platinumrock]

I just bought a little UV flashlight to test fluoro on my colored diamonds. Is it me or do you guys kind of feel it on your skin? At least when the light hits your skin. It''s hard to describe it but it feels like something is penetrating your skin. Sort of like a faint burning sensation.

I also feel this when I make copies and my hand touches the glass.

Does this mean the scanner light is a UV source as well?

 

[T L]

Date: 12/2/2009 10:21:09 PM
Author: platinumrock
I just bought a little UV flashlight to test fluoro on my colored diamonds. Is it me or do you guys kind of feel it on your skin? At least when the light hits your skin. It''s hard to describe it but it feels like something is penetrating your skin. Sort of like a faint burning sensation.

I also feel this when I make copies and my hand touches the glass.

Does this mean the scanner light is a UV source as well?

PR,
What kind did you buy? My little keychain UV light has a thick glass casing over the LED, and it doesn''t hurt my skin or eyes.

 

[T L]

Date: 12/2/2009 2:00:25 PM
Author: Stone Hunter

Well I bought a ''black light'' from Spensers but it''s just a regular light bulb with a black coating and it doesn''t make my stones show their Fluor. Your black light torch must be different.

Now that I''ve found out that Sapphires can have Fluro I need to check all of my stones. Maybe I''ll be pleasantly suprised!

I don''t know about Discos being allowed to use UV lights but I do trust Disney more than Discos. Which means that I need to either buy a ''black light'' online or take all my stones to Disney!

Some garnets even fluor. My grossular minty garnet fluors red. I was quite shocked when I saw that, but I heard it was from the chromium content. I have heard some tsavorites fluor as well. Not all though.

 

[platinumrock]

Date: 12/2/2009 10:34:45 PM
Author: tourmaline_lover

Date: 12/2/2009 10:21:09 PM
Author: platinumrock
I just bought a little UV flashlight to test fluoro on my colored diamonds. Is it me or do you guys kind of feel it on your skin? At least when the light hits your skin. It's hard to describe it but it feels like something is penetrating your skin. Sort of like a faint burning sensation.

I also feel this when I make copies and my hand touches the glass.

Does this mean the scanner light is a UV source as well?

PR,
What kind did you buy? My little keychain UV light has a thick glass casing over the LED, and it doesn't hurt my skin or eyes.

It's a flashlight that can be switched to regular light, laser and uv. The diamonds look so cool with the laser pointer! They literally glow red!

Here's the Ebay listing link. (Hong Kong)



ETA: TL, I gave you the wrong seller that I bought from. Sorry. I just did a quick Ebay search and my above link looked similar to the listing I bought from. This is the seller I bought from, and he shipped it within hours of my payment. And he's in California. I'm in Florida. Shipping is free. Regular first class. And it arrived in 4 days!

The Ebay Listing that I purchased from. (California)

 

[T L]

Date: 12/2/2009 10:41:42 PM
Author: platinumrock

Date: 12/2/2009 10:34:45 PM
Author: tourmaline_lover

Date: 12/2/2009 10:21:09 PM
Author: platinumrock
I just bought a little UV flashlight to test fluoro on my colored diamonds. Is it me or do you guys kind of feel it on your skin? At least when the light hits your skin. It''s hard to describe it but it feels like something is penetrating your skin. Sort of like a faint burning sensation.

I also feel this when I make copies and my hand touches the glass.

Does this mean the scanner light is a UV source as well?

PR,
What kind did you buy? My little keychain UV light has a thick glass casing over the LED, and it doesn''t hurt my skin or eyes.

It''s a flashlight that can be switched to regular light, laser and uv. The diamonds look so cool with the laser pointer! They literally glow red!

Here''s the Ebay listing link.

Thank you PR. That one looks more powerful than my little keychain light. I should try it.