Phosphorescence in Diamonds-Study, and a request for sharing information

[Sithathoriunet]

flur. Those are gorgeous! As is the Aurora collection. I don't have anything quite as beautiful, but I do have a couple pictures. The top picture left to right is a chameleon, the fancy green yellow with strong blue fluorescence (the one that phosphoresces but I can't get a picture of that), and my fancy intense green yellow with strong green fluorescence. The bottom picture is the fancy green yellow, the fancy intense green yellow, and a fancy yellow.

Your gems are beautiful! Thank you for the pictures! And you have a chameleon! That is very cool! I have always been fascinated by them.. I don't have any more diamonds that show either fluorescence or phosphorescence just the inert kind..lol I don't know how Roselina managed to photograph her diamond phosphorescing but maybe she could let us know so we could try to capture our little night lights?
All I have is my phone for a camera and it just doesn't seem to be able to do that...
The pictures I had from before were taken by a photographer friend who was curious to see if he could capture the effect..

 

[Sithathoriunet]

OK - you asked for it - i will invite G to join up. He is a retired scientist.
We are lunching at Ewen Tylers invitation on Tuseday. Ewen led or was involved with the discovery of all 3 commercial diamond mines in Australia: Ellendale (Tiffany had first dibs on the yellow diamonds) Argyle, and Merlin - 105ct rock found. Ewen features in a book to be available next month about Argyle.

Hi Gerry! WOWOWOWOW!!! This is AMAZING! Thank you! I read this and I must say, it will take another read, because from a relatively lay type perspective, some of the info is a little complicated to wrap my thoughts around.And I love that!!
I am so very appreciative that you are sharing this with everyone...
Looking so forward to the expansion of this topic and finding out how charging these little night lights can help them to glow longer and brighter in some cases, while not in others.
Thank you!!

 

[Tourmaline]

I have some small diamonds that fluoresce blue and phosphoresce orange. I see that others have mentioned that, too. The phosphorescence can last all night.

 

[Sithathoriunet]

I have some small diamonds that fluoresce blue and phosphoresce orange. I see that others have mentioned that, too. The phosphorescence can last all night.

Hello Tourmaline, this is soooo cool! So your diamonds can phosphoresce all night? Can I ask you if this requires an extended charge time? Am I correct in assuming that the uv type that gives your gems their charge is shortwave? And the longer they are exposed, the longer they can phospheresce? Your diamonds are beautiful!

 

[Sithathoriunet]

 

[silkystarlight]

Yes!!! The more magic gems the better!

Thank you so much for the insight! "echo chamber of luminosity"- I love this terminology! The way you theorized the amplification effect makes sense and also makes me think that this ability of prolonged phosphorescence could be prevalent in these fancy white diamonds....oh oh...I may need to buy another one to test now....lol

Sooo it turns out that to get the desired visuals I'm looking for, I'm probably going to be using Fancy White diamonds in my ering/wband... (I have a whole thread about it if you have any interest in what I have in mind for the project) so we could go diamond hunting together! I'm honestly even more excited now about the idea of working with Fancy Whites now that I know they potentially produce much more intense fluorescence/phosphorescence... I'm gonna harness all that magic and make some super rings!!

this just cracks me up!!

 

[Sithathoriunet]

Sooo it turns out that to get the desired visuals I'm looking for, I'm probably going to be using Fancy White diamonds in my ering/wband... (I have a whole thread about it if you have any interest in what I have in mind for the project) so we could go diamond hunting together! I'm honestly even more excited now about the idea of working with Fancy Whites now that I know they potentially produce much more intense fluorescence/phosphorescence... I'm gonna harness all that magic and make some super rings!!


this just cracks me up!!

Super rings!!!! Yes! Im in!!! Im going over to check out your thread...I sent out some messages to sellers with fancy whites last night asking them to let me know if their gem has the ability to be a night light, one got back to me already and said that theirs has "weak phosphorescence" so, Im gonna say that so far, the odds look promising that fancy whites have this ability! OMG, Im so excited to do more research and find out if they are the magic gem of night lights...
My theory thus far is that because of the microscopic inclusions which produce the "whiteness" -the more "white" or opaque, the better they phosphoresce? hummmmmm

 

[Demon]

Your gems are beautiful! Thank you for the pictures! And you have a chameleon! That is very cool! I have always been fascinated by them.. I don't have any more diamonds that show either fluorescence or phosphorescence just the inert kind..lol I don't know how Roselina managed to photograph her diamond phosphorescing but maybe she could let us know so we could try to capture our little night lights?
All I have is my phone for a camera and it just doesn't seem to be able to do that...
The pictures I had from before were taken by a photographer friend who was curious to see if he could capture the effect..

Yeah, I'm just using my phone too. I think its amazing that yours glows for so long. I don't know how they make glo sticks, but I wonder if they could put whatever it is that makes glow in the dark things glow for so long, into lab grown diamonds. Wear it under a light for a bit and it would glow all night?

 

[Garry H (Cut Nut)]

In my parallel universe here is a snippet from another much published seriously smart gemologist:
As you are all aware, what we humans see as fluorescence is only part of the picture. Then comes the various fascinating aspects of Stokes and anti-Stokes fluorescence. The plethora of PL reactions as the energy waves are introduced causes effects often only seen on spectrometers. Excited electrons that can either make their way to another stage, or get bogged up by running into other elements (like Fe) on their way.

 

[Sithathoriunet]

Yeah, I'm just using my phone too. I think its amazing that yours glows for so long. I don't know how they make glo sticks, but I wonder if they could put whatever it is that makes glow in the dark things glow for so long, into lab grown diamonds. Wear it under a light for a bit and it would glow all night?

That would be amazing! The marketing would be fun too..lol
I think investigating more how this super charge long lasting glow thing comes about will be fun... We need everyone to go buy uv lamps..lol

 

[Sithathoriunet]

In my parallel universe here is a snippet from another much published seriously smart gemologist:
As you are all aware, what we humans see as fluorescence is only part of the picture. Then comes the various fascinating aspects of Stokes and anti-Stokes fluorescence. The plethora of PL reactions as the energy waves are introduced causes effects often only seen on spectrometers. Excited electrons that can either make their way to another stage, or get bogged up by running into other elements (like Fe) on their way.

This fascinates me, the actual mechanics of how this happens..I just looked up the meaning of " Stokes and anti-Stokes fluorescence"...very cool. Further reading required..lol
Thank you!

 

[Garry H (Cut Nut)]

This fascinates me, the actual mechanics of how this happens..I just looked up the meaning of " Stokes and anti-Stokes fluorescence"...very cool. Further reading required..lol
Thank you!

Yes - I am learning too.
Any chance your diamond gets cooler as it emits light?
Anti Stokes fluorescence / phosphorescence!!!!
Imagine diamond refrigerator that would cool when sunlight shone on it!!!

 

[silkystarlight]

Super rings!!!! Yes! Im in!!! Im going over to check out your thread...I sent out some messages to sellers with fancy whites last night asking them to let me know if their gem has the ability to be a night light, one got back to me already and said that theirs has "weak phosphorescence" so, Im gonna say that so far, the odds look promising that fancy whites have this ability! OMG, Im so excited to do more research and find out if they are the magic gem of night lights...
My theory thus far is that because of the microscopic inclusions which produce the "whiteness" -the more "white" or opaque, the better they phosphoresce? hummmmmm

oooooh I can't wait to hear what the rest of the sellers you messaged have to say!! And as far as educated guesses go, I feel like you have a pretty strong one going here! It wouldn't surprise me at all if the microscopic inclusions that make the silky haziness had a hand in some of the phosphorescence... if anything I think I'll be very confused if it turns out there is zero correlation!

quick, we need to get some fancy whites so we can do an official experiment! it'll be science (and therefore a perfectly good excuse) as long as we remember to write it all down!

 

[Sithathoriunet]

oooooh I can't wait to hear what the rest of the sellers you messaged have to say!! And as far as educated guesses go, I feel like you have a pretty strong one going here! It wouldn't surprise me at all if the microscopic inclusions that make the silky haziness had a hand in some of the phosphorescence... if anything I think I'll be very confused if it turns out there is zero correlation!

quick, we need to get some fancy whites so we can do an official experiment! it'll be science (and therefore a perfectly good excuse) as long as we remember to write it all down!

That is exactly my feeling!! LOL, totally for science...Two of the sellers are currently checking the milky whites that they have, and will let us know.. One of them has confirmed very strong white fluorescence so far...
This will be the hard part-once we know if this phosphorescing ability is prevalent in fancy whites, not actually buying all of them...lol

 

[Sithathoriunet]

I had this article from a long while ago, and it mentions the lasting phosphorescence and when different types of light turn it off essentially...I couldn't upload the pdf, so I am cut and pasting here..sorry for the long post..

THE PHOSPHORESCENCE OF DIAMOND

BY V. CHANDRASEKHARAN (From the Department of Physics, Indian Institute of Science, Bangalore) Received June 15, 1946

(Communicated by Sir C. V. Raman, KT, F.R.S., N.L.)

1. INTRODUCTION A REMARKABLE property of many diamonds is their power to store up energy under ultraviolet irradiation, a portion of which is released as visible light on shutting off the exciting radiation. This phenomenon, known as phosphorescence, has been remarked upon by several early workers like Robert Boyle, Crookes, Becquerel and others. However, the rest of the energy is retained in the diamond even for several days and released as visible light on either heating or more effectively on re-illuminating the diamond with long wavelength radiations even at or below room temperature. The former effect of heating has been dealt with in the paper on thermoluminescence appearing in the present symposium, while the latter is mainly dealt with in this paper. The main facts about phosphorescence already summarized in the paper referred to are also presented here more fully.
Diamonds which show bright blue fluorescence under ultraviolet light exhibit a greenish-yellow afterglow for about 30 minutes in which there is also a blue component during the first few seconds. Sir C~ V. Raman discovered this fact by the use of a violet filter and this technique of viewing the diamond through filters has been found extremely useful in studying the effect of re-illumination. The green-fluorescent diamonds show only a feeble phosphorescence. When blue-fluorescent diamonds after exposure to ultraviolet light are re-illuminated with red light and viewed through a filter complementary to the red, a very bright blue flash is observed which dies away in a few minutes. In the case of green-fluorescent diamonds, the flash is green. Both varieties of diamonds on heating lose their activation in the form of thermoluminescence. Ultraviolet light below 3000A produces activation several times greater than that produced by radiation between 3500 and 4000 A. X-rays are also able to produce a slight activation. Any wavelength above 4200 A is able to remove the activation in diamonds.

2. PHOSPHORESCENCE The main facts about the phosphorescence of diamonds have already been stated in the paper on thermoluminescence appearing in the present symposium.
As the specimens N.C. 67, N.C. 68, and N.C. 41 have been used in the study of re-illumination with long wavelength radiators, their phosphorescence is described below. The former two are small brilliants and are intensely blue-fluorescent, while N.C. 41 is a moderately large crystal which is brightly green-fluorescent. N.C. 67 and N.C. 68 after exposure to ultraviolet light of the sun exhibit a greenish yellow glow and the change of colour from the blue fluorescence to greenish yellow phosphorescence is very striking.

To find whether any blue phosphorescence is present in the glow, the diamond is viewed through a violet filter having a cut-off between 4950 and 6300 A; a faint glow is then detected lasting for about 20 seconds. The main bulk of the emitted energy is, however, in the yellow, as the brightness of the glow is practically undiminished by the interposition of a yellow filter transmitting wavelengths greater than 5000 A. The green fluorescent diamond shows a faint greenish yellow glow lasting for about 40 seconds which is, however, too faint to be studied with filters.

It is found that the decay of the afterglow in all cases is extremely rapid in the first few seconds. It is proposed to take up the exact nature of the decay in a further communication.

The fluorescence spectra of diamonds taken by Miss Mani (1944) reveal mainly a line at ^ 4152 and a system of bands associated with it and also another line at ^ 5032 and an accompanying band system. In the phosphorescence spectrum of N.C. 68 taken by Miss Mani (unpublished work), both systems appeared. As the time interval between irradiation and exposure was only a fraction of a second, the violet phosphorescence was present and was recorded as the 4152 system. The green glow may be identified with the 5032 system which presumably has a long lifetime in the phosphorescence of blue-fluorescent diamonds.

3. THE EFFECT OF RED LIGHT In order to follow the effect of re-illumination, it is important to recall the Stokes law of fluorescence. The wavelength of the exciting radiation should be near about or less than the wavelength of fluorescence. Thus red light is unable to excite any visible fluorescence, and similarly green light cannot produce any violet fluorescence.

Blue-Fluorescent Diamonds.--The diamond N.C. 67 is exposed to ultraviolet light of the sun for about a minute and after shutting it off, red light obtained by passing sunlight through a red filter transmitting above 6300 A is focused on it. On viewing the diamond through a 3 cm filter of saturated copper sulphate solution which is complementary to red light, a bright blue flash is observed which decays very rapidly in the beginning and is visible for about four minutes. As red light cannot produce a fluorescence, the flash is due to the release of the stored-up energy in the diamond by red light. Even though the colour of the flash is blue, it also contains wavelengths from 5000 to 6000 A. This is shown by the fact that the glow can be observed both through a blue filter of ammoniacal copper sulphate solution transmitting wavelengths less than 4600 A and through a green filter transmitting 5000 to 6000 A.

On illuminating the activated diamond with green light (5000 to 6000/~) of the sun and observing through a complementary violet filter, a bright violet flash is observed for about two seconds, and subsequently there is a persistent faint red colour due to fluorescence produced by the green light. The violet flash is, however, due to the release of activation energy by the green light as is indicated by the decaying of the flash.

The effect of both green light and red light can be noticed even a few days after activation by ultraviolet light. This indicates that the stored-up energy is retained by the diamond, and is released by exposure to green light for a sufficient time, since red light has subsequently no effect ; also, vice versa.

Blue light (4100 to 5000 A) for about a minute, any flash occurring during the exposure cannot be observed through a complementary filter owing to the presence of a persistent green and red fluorescence produced by blue light. However, after such exposure, the diamond no longer shows any flash on irradiation with red light, thereby indicating that blue light is able to remove the stored-up energy presumably as a flash. Using a monochromator with sunlight as the source, a preliminary study of the efficiency of different wavelengths in removing the activation in the blue-fluorescent diamond N.C. 68 has been made. Green light near about ^ 5500 appears to be the most efficient, but a more thorough examination of the facts will be published later. It is also found that for a given wavelength, the brightness of the flash increases with intensity of the light used while the duration of visibility diminishes, showing that the whole of the stored-up energy is released in a shorter interval of time by a more intense source of light.

The activation in diamond is increased on increasing the intensity of the activating ultra-violet light. However, as in the case of phosphorescence, the time of irradiation need only be a second. Increased exposure times do not result in an observable increase in the intensity of the flash which results from illuminating the diamond with a constant source of red light.

When the radiations from a low pressure quartz mercury arc are used for activation, it was found that the blue flash obtained by subsequent irradiation with red light (above 6800 A) is much brighter than when the near ultraviolet between 3500 and 4000 A is employed for activation. In fact, the blue colour is clearly seen for a few seconds even in the presence of the intense red light in the former case, while a filter of copper sulphate solution has to be used to cut out the red light if the blue flash is to be observed in the latter case.
A very large part of the high activation produced by the quartz mercury arc is due to radiations below 3000 A. This is shown by the fact that when a glass plate which cuts off these wavelengths is interposed between the diamond and the mercury arc, the activation is reduced to a very small fraction of its former strength. It is also found that subsequent exposure to light between 3500 and 4000 A reduces the large activation produced by radiations below 3000 A.

During any part of a flash if the illuminating light is cut off, the flash disappears instantaneously as far as the eye can judge. The remaining part of the flash can be completed at any later time by illuminating again with the light.

X-rays are also able to produce a slight activation. This can be verified by removing all previous activation in the diamond by exposure to bright red light for about half an hour and then irradiating it with X-rays for a few seconds. Subsequently, when red light is allowed to fall on the diamond, a feeble blue flash is observed through the copper sulphate filter.

Green-fluorescent Diamonds.--The green fluorescent diamond N.C. 41 behaves in exactly the same way with regard to all the above effects except for the fact that the flash is green as observed through copper sulphate solution and not blue. The major portion of the energy of the flash is hence in the green.

Spectrum of the Flash.--The diamond N.C. 67 after activation by focusing the light of a quartz mercury are on it with a quartz lens, was placed very close to the slit of a Zeiss three-prism spectrograph. The light of a carbon arc was passed through a red filter transmitting wavelengths greater than 6300A and focused on the diamond. After one minute of exposure, the diamond was activated again and the experiment repeated 30 times. A faint spectrum (not reproduced) was obtained in the violet part and showed the 4152 line and its system of bands. To prove that the spectrum was not due to fluorescence, a bIank experiment was performed in which the diamond was not activated with the mercury arc but a continuous exposure of one hour and a half was given with red light focused on the diamond as before. In the spectrum, no trace of the violet portion was found and only the band in the red region due to the incident light appeared.

In the case of the brightly green-fluorescent diamond N.C. 41, the 5032 line and its bands were found faintly with an exposure repeated 50 times in the manner described above.

4. THE EFFECT OF HEAT It has been stated that the diamonds retain energy for several days after activation. The activated blue-fluorescent diamonds on heating to 270 C. exhibit blue thermoluminescence as stated in the paper on thermoluminescence. After a few minutes the glow disappears, and after cooling the diamond shows no longer any flash on irradiating with red light and observing through copper sulphate solution. In the case of the green-fluorescent diamond N.C. 41, a faint greenish yellow thermoluminescence is observed on heating to 270C. and subsequently the usual flash with red light is absent. Thus at 270C. the diamonds lose their activation.

On cooling the diamonds by immersing in liquid air, they showed every one of the usual effects resulting from activation.

In conclusion the author wishes to express his deep gratitude to Professor Sir C. V. Raman for his inspiring guidance and for his helpful interest in the problem.

5. SUMMARY Fluorescent diamonds retain some energy after ultraviolet irradiation, a part of which is released at room temperature as phosphorescence. However, a greater part of the energy remains with the diamond for any length of time until it is illuminated with long wavelength radiations; it is then emitted as a flash of visible light. This can be observed through a proper filter complementary to the illuminating light. Any wavelength above 4200A is able to remove the activation in diamonds. Ultraviolet light below 3000 A produces activation several times greater than that produced by the very near ultraviolet between 3500 and 4100 A. X-rays are also capable of producing a weak activation. All these effects are observed even at liquid air temperature. However, the activation in diamond can be removed by heating it to 270 C. when thermoluminescence is observed. In the case of blue-fluorescent diamonds, the stored-up energy is given out mainly as a blue flash on illuminating them with long wavelength radiations and the spectrum of the flash reveals mainly the 4152 system, while in green-fluorescent diamonds, green light is mainly emitted and the 5032 system is found in the spectrum of the flash.

REFERENCES Anaa Mani .. Proc. lnd. Aead. Sci.,

 

[Sithathoriunet]

Yes - I am learning too.
Any chance your diamond gets cooler as it emits light?
Anti Stokes fluorescence / phosphorescence!!!!
Imagine diamond refrigerator that would cool when sunlight shone on it!!!

Hummmmm, this I have not experienced. I will charge it tonight and let you know.. That would be a diamond worthy of becoming part of marvel comics as a talisman or sort of "green lantern" ring!

 

[Sithathoriunet]

I was completely excited to see that the GIA had a chart they put up with gem phenomena, so of course I saved it to include here...but they completely omitted Fluorescence and Phosphorescence! Do they not count as a type of phenomenon?

 

[silkystarlight]

That is exactly my feeling!! LOL, totally for science...Two of the sellers are currently checking the milky whites that they have, and will let us know.. One of them has confirmed very strong white fluorescence so far...
This will be the hard part-once we know if this phosphorescing ability is prevalent in fancy whites, not actually buying all of them...lol

oooooh that is exciting! Would love to see pics if the sellers are willing to share.

and oh man I know right?? I'm having a hard enough time as it is not just buying up lots of pretty silky stones, let alone diamonds!

 

[Sithathoriunet]

I thought I could capture the opalescence in the sun yesterday, but as it turns out, it is challenging, what the human eye sees is apparently not what the cell phone camera sees...Its about as difficult as capturing the rainbow flash in a colorless diamond..

 

[Sithathoriunet]

I just heard back from one of the sellers with the fancy whites, he has confirmed that there is no phosphorescence, the diamond does fluoresce, but after the uv is turned off, the diamond stops glowing. Well, that is disappointing! I was thinking that perhaps it may be a trait in fancy whites, so I will keep everyone posted as more responses come in..
As I write this I suspect that he may be using LW UV, not SW UV..I will follow up with him to be sure.

 

[Texas Leaguer]

@Sithathoriunet ,
Don't know if you have seen this article, but I thought you might find it interesting.

Natural-Color Fancy White and Fancy Black Diamonds: Where Color and Clarity Converge | Gems & Gemology

A systematic study of the properties of approximately 500 Fancy white and 1,200 Fancy black diamonds.

www.gia.edu

 

[Sithathoriunet]

@Sithathoriunet ,
Don't know if you have seen this article, but I thought you might find it interesting.

Natural-Color Fancy White and Fancy Black Diamonds: Where Color and Clarity Converge | Gems & Gemology

A systematic study of the properties of approximately 500 Fancy white and 1,200 Fancy black diamonds.

www.gia.edu

Thank you for sharing this article! It will be a fascinating read I'm sure!

 

[munchee]

Thank you OP for sharing this interesting facts! I would never know these facts if you didn’t share this info!

 

[Sithathoriunet]

@Sithathoriunet ,
Don't know if you have seen this article, but I thought you might find it interesting.

Natural-Color Fancy White and Fancy Black Diamonds: Where Color and Clarity Converge | Gems & Gemology

A systematic study of the properties of approximately 500 Fancy white and 1,200 Fancy black diamonds.

www.gia.edu

That was a very interesting read! And they do mention the effects of LW on these diamonds..Too bad they didn't get to the phosphorescence! In any case, it certainly shows the rarity of the fancy whites, and I am amazed at the depth at which they are said to have had to form! Awesome!!! Thank you!

 

[Sithathoriunet]

The article mentioned above has a very interesting chart they put together on the fluorescence of fancy white diamonds, they do not go so far as to investigate phosphorescence, but this is a great start!

 

[Garry H (Cut Nut)]

I thought I could capture the opalescence in the sun yesterday, but as it turns out, it is challenging, what the human eye sees is apparently not what the cell phone camera sees...Its about as difficult as capturing the rainbow flash in a colorless diamond..

We have 2 eyes - so we see twice as much opalescence (and fire) - so 3D virtual camera will work - but practically a video will work way better than a still shot.

 

[Sithathoriunet]

We have 2 eyes - so we see twice as much opalescence (and fire) - so 3D virtual camera will work - but practically a video will work way better than a still shot.

Noted, thank youi will give it a try...my cell is pretty old, so we will see..i may need to buy a newer version...

 

[Sithathoriunet]

Yes - I am learning too.
Any chance your diamond gets cooler as it emits light?
Anti Stokes fluorescence / phosphorescence!!!!
Imagine diamond refrigerator that would cool when sunlight shone on it!!!

Reporting back about the fancy white's temperature while phosphorescing. It seems to remain cool, but not get cooler while glowing. Of course I am only using my fingers to 'test' this, so if someone tested it with actual equipment I suppose this could be overturned..lol

 

[Sithathoriunet]

I heard back from the only seller who has answered me about if the fancy white they are selling can phosphoresce, he was the one who stated that it fluoresces strongly blue.
I asked him if he had tested it with SW UV and he seemed perplexed like he had never done this. he even shared with me the LW lamp type he uses to test for this, and I mentioned to him that you must test with a SW lamp to see if the diamond can phosphoresce..I don't think he will do this because he will need to get one of these in order to test. So, it may be a while if no one tests for this phenomena regularly..

 

[Garry H (Cut Nut)]

Sithathoriunt. You should never assume diamond sellers know or care about diamonds.
Sadly. (does that mean South of the Orient?

Unrelated, but I was given a crazy UV lamp yesterday.
It is perfect for making blue fluorescence: