Author Topic: Diamond Fluorescence  (Read 5042 times)

Offline flyingdiamonds

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Diamond Fluorescence
« on: February 03, 2012, 06:47:34 PM »
I Just discovered something pretty interesting!
I have a small little UV light and in the dark i held it up close to my diamond rings.  The rings i did this two included a 7 stone channel set FY  ring, a 7 stone round M colored band as well as a band of small pinks.  When I held the UV light up the the stones some clearly had a bit of blue fluorescence - which was cool to see but when you put the light up to the stone and hold it for three second and then remove the light (in a dark room) the diamonds which fluorescence continue to GLOW!  For about 5 seconds - then fade to nothing!

Why does the stone continue to glow and should this property decrease the value of the stone?  Two of the rings were made of stones from parcels - i never thought ask if each stone has fluorescence - should i have?  Surprisingly the stones that I paid a fair bit for have the most fluorescence... the ebay cheapies fluoresce but don't glow....

I will try and post some pictures... the first is before, the second with the UV light and the third with the UV off....

« Last Edit: February 03, 2012, 06:49:09 PM by flyingdiamonds »

Offline DiamondsAreForever

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Re: Diamond Fluorescence
« Reply #1 on: February 03, 2012, 07:13:09 PM »
FD, that is totally cool!  I have an UV light that I've checked my diamonds with, but I've never tried to see who glows in the dark.  Absolutely Neat!

Offline Sanchica27

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Re: Diamond Fluorescence
« Reply #2 on: February 03, 2012, 09:23:36 PM »
That's awesome!
always saving up for my next piece!

Offline clgwli

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Re: Diamond Fluorescence
« Reply #3 on: February 04, 2012, 12:03:18 AM »
It's late for me and I have only started reading more on this subject lately but what you are seeing is called Phosphorescence.  For example I know the Hope Diamond will glow reddish for a while after UV light has been exposed to it.  Hopefully someone with way more knowledge than I have will be able to comment more.  It is a really cool effect though!
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Offline Trinkette

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Re: Diamond Fluorescence
« Reply #4 on: February 04, 2012, 11:10:55 AM »
Thank you for the photos, Flyingdiamonds. I wish they were a bit larger so I could SEE these cool effects a little better! FWIW, fluorescence and phosphorescence are not bad at all. In fact, with only a few exceptions, they are considered desirable in diamonds.

Here's my shot at this:

When illuminated by UV light, some diamonds absorb high-energy radiation and re-emit it as visible light. This is fluorescence. Fluorescence is most commonly blue, but may appear in other colors, including white, green, yellow or orange. Several different fluorescent color zones may occur within one stone (need special equipment to see this).

Many people, including pros, prefer fluorescence in their diamonds, especially blue fluorescence in colorless and near-colorless stones.  Blue fluorescence in these diamonds can make them appear a more highly desired “blue-white,” and really brighten stones in daylight, when non-fluorescing diamonds may appear darker.

However, yellow or orange fluorescence in a high-color stone may make the diamond appear less “white,” so this type of fluorescence is not necessarily a desired trait. It depends upon the body color of a particular diamond.

In colored stones, one should be aware if there is a very strong fluorescence in a color that is opposite the color of the stone. For example, the perceived color of a Fancy yellow diamond might be impacted by a very strong blue fluorescence because on the color wheel, blue is opposite yellow. So when the yellow stone with blue fluorescence is viewed in daylight, the two colors may cancel each other out, creating… "meh" in terms of color. On the other hand, yellow, orange, or even green fluorescence may actually enhance the appearance of a yellow diamond by intensifying the appearance of the yellow body color. This "color boost" can really be a benefit to faint and light yellow stones, for example. I'd even venture to say that a lower-alphabet light yellow diamond with medium or strong yellow or orange fluorescence could give quite a color punch while saving a bundle in terms of cost.

According to the GIA, between 25 and 35 percent of all gem-quality diamonds show fluorescence. Of these, a mere 0.2 percent show extreme fluorescence which gives diamonds a milky or greasy appearance. Because of their cloudy appearance, these few diamonds may be considered less desirable than stones with less fluorescence.

Diamonds that have “fluorescence” on their grading reports generally cost less than diamonds without fluorescence, regardless whether the fluorescence impacts appearance positively or negatively.  This is because, as cool as it can be, explaining fluorescence to most shoppers is difficult and there doesn’t seem to be much of a benefit to the average buyer.

A rare number of diamonds that show fluorescence continue glowing after removal of the UV source. These diamonds are phosphorescent. Coveted Type IIb diamonds, which are semiconductive, often display phosphorescence. As clgwli wrote, the Type IIb Hope and Wittelsbach-Graff diamonds, both from India in the 17th century, show orange-red phosphorescence.

Offline flyingdiamonds

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Re: Diamond Fluorescence
« Reply #5 on: February 04, 2012, 02:29:47 PM »
So its not a bad thing after all!   I have to admit I love things that glow in the dark and this is pretty cool!  I have a FLY diamond that is med fluor (GIA grading) i should check to see what it looks like tonight.

Thanks for all your great info!
Its hard to take pictures in the dark and you have to make them so tiny to be uploaded on the site... Unless I was doing it wrong....

thanks again!

Offline oldmancoyote

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Re: Diamond Fluorescence
« Reply #6 on: February 04, 2012, 03:08:15 PM »
Don't upload them to the forum - use PhotoBucket, Picasa or a.n.other web storage site, then link them to the post using [ img ] tags (without the spaces). This way there is no limit on size.

Offline dovesgate

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Re: Diamond Fluorescence
« Reply #7 on: February 04, 2012, 11:34:46 PM »
I googled an image for the Hope diamond's phosphorescence. Wow!!

Flyingdiamonds, that is such an interesting feature to your rings. Thank you for sharing the pictures!

Offline Mrs Mitchell

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Re: Diamond Fluorescence
« Reply #8 on: February 06, 2012, 01:35:26 PM »
Very cool! I LOVE fluorescence and would always pick the stone with over the one without. I think it's fascinating.
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Offline Sweet Pea

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Re: Diamond Fluorescence
« Reply #9 on: March 30, 2012, 01:15:17 PM »
Very cool! I LOVE fluorescence and would always pick the stone with over the one without. I think it's fascinating.

Me too, Mrs. M!

And I think I'd pay extra for one that would continue to glow afterward.

I once had an engagement ring with a FLY diamond as the center stone framed in an rather rococo micropave setting.  The center stone had medium blue fluorescence but it didn't detract from the yellow one bit that I could tell -- that Tweety bird could sing!   :tweety:

The cool thing was I noticed that, in addition to the ghostly greenish glow from the center stone under my UV light (352 nm), 3 or 4 of the pave stones were glowing, and one of them was glowing a lovely salmon *pink* of all things.

*That* one continued to glow for about 10 seconds even after I turned off the UV light.

It was a cool ring.  Alas, when I tossed the guy back  :snake: (cheater, cheater, pumpkin eater - ugh!),  :snake: I tossed the ring right after him so there wouldn't be any reason at all for him to be hanging around and bothering me.
"I will put the diamond chain round your neck, and the circlet on your forehead, which it will become: for Nature...has stamped her patent of nobility on this brow, Jane; and I will clasp the bracelets on these fine wrists, and load these fairy-like fingers with rings." ~ Edward Rochester, Jane Eyre

Offline Dresden

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Re: Diamond Fluorescence
« Reply #10 on: June 15, 2012, 10:23:22 PM »
 8) 8) How cool!  8) 8)

All this Flourescence stuff is really making the newbie want to know more...


So, how can we get a white Diamond to look Blue?

Offline jackhavel

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Re: Diamond Fluorescence
« Reply #11 on: July 17, 2012, 04:46:39 AM »
I Just discovered something pretty interesting!
I have a small little UV light and in the dark i held it up close to my diamond rings.  The rings i did this two included a 7 stone channel set FY  ring, a 7 stone round M colored band as well as a band of small pinks.  When I held the UV light up the the stones some clearly had a bit of blue fluorescence - which was cool to see but when you put the light up to the stone and hold it for three second and then remove the light (in a dark room) the diamonds which fluorescence continue to GLOW!  For about 5 seconds - then fade to nothing!

Why does the stone continue to glow and should this property decrease the value of the stone?  Two of the rings were made of stones from parcels - i never thought ask if each stone has fluorescence - should i have?  Surprisingly the stones that I paid a fair bit for have the most fluorescence... the ebay cheapies fluoresce but don't glow....

I will try and post some pictures... the first is before, the second with the UV light and the third with the UV off....


I have never seen a diamond glowing like this in the dark. It is looking very beautiful.
Thanks.