Fancy light blue diamond with GIA report of origin listed as "undetermined"

[pinkjewel]

Based on my experience....some cutters re-submit repeatedly to challenge an undetermined comment. Sometimes shipping the stone across the globe to submit to a different GIA branch....
I don't recall a case of GIA reversing an "UNdetermined"...of course, it may have happened regardless...

Regarding Natural Blue Diamonds and fluorescence:
Based on a much larger sample size.
Of 80 diamonds graded Fancy Light Blue, Fancy Blue, and Fancy Intense Blue by GIA, only one stone -a Fancy Light Blue- had Stong Blue. Three of the stones had "Faint" fluorescence. So I guess I have to eat my words

Blue stones with modifiers, different story.
Strong Blue is common in Green, or Greenish blue diamonds, for example.
Gray-Blue Diamonds also exhibit fluorescence more commonly.
of the stones graded "Fancy Blue" had any fluorescence.

Yup- my fancy green blue diamond has blue fluorescence- I'd have to dig out the report to see how strong the fluorescence is as I don't remember off the top of my head.

 

[Demon]

From John Chapman (Argyle's Ex Scientist)
Yes Argyle and Boron blues do fluoresce differently. Argyle’s yellowy-blue and boron weak red and also red phosphorescence. CVD blue fluoresce strong blue. Well I think they do, certainly the HPHT ones do.
I checked several listed on PS and most were CVD IIa so not blue as grown - post treated and they had none.

Thanks

 

[Rockdiamond]

CVD blue fluoresce strong blue. Well I think they do, certainly the HPHT ones do.

Garry!!
Buddy!!!
Mate!!!
Sorry, but this is incorrect.
The proponents of HPHT will tell you they grow totally colorless, with no post growth treatments. None ( that I've seen) possess any fluorescence.


The only CVD's that I have seen which possess fluorescence are CVDs that have been treated to turn pink- in which case they generally possess Orange Fl.

 

[Garry H (Cut Nut)]

Sorry, but this is incorrect.
The proponents of HPHT will tell you they grow totally colorless, with no post growth treatments. None ( that I've seen) possess any fluorescence.


The only CVD's that I have seen which possess fluorescence are CVDs that have been treated to turn pink- in which case they generally possess Orange Fl.

Hi Buddy from your mate
We are talking about diamonds with blue color, not colorless.
And this was from John Chapman who makes:

Gemetrix Pty Ltd - for diamond industry consulting and gemmological products

Gemetrix Pty Ltd, offering consulting to the diamond and related industries, also gemmological products, including custom instrumentation and a pocket-sized product for determining the difference between natural and synthetic diamonds.

www.gemetrix.com.au

that is also sold by the other leading dude in the field:

Jewellery Inspector - Branko Gems - Gemmological Research Industries Inc.

The Gemetrix Jewellery Inspector allows observation of the SW and LW UV reactions, including phosphorescence, of diamonds set in jewellery (or loose).

www.brankogems.com

 

[Rockdiamond]

The single "Born Blue" we submitted came back inert

GIA - Report Check

www.gia.edu

None of the treated blues we've had have exhibited any fluorescence

 

[Ella]

A gentle reminder that we don’t allow posting personal contact information on the forum for everyone’s safety.

 

[nojs]

Here's an article you fancy color nerds will enjoy

Hope Diamond's Fiery Red Phosphorescence Key To Fingerprinting

Shine a white light on the Hope Diamond and it will dazzle you with the brilliance of an amazing blue diamond. Shine an ultraviolet light on the Hope Diamond and the gem will glow red-orange for about five minutes. This phosphorescent property of blue diamonds can distinguish synthetic and...

www.sciencedaily.com

This must not be correct regarding other colours not having phosphorence. I have been able to make my white diamonds phosphorence by "loading" when with a UV torch for a few minutes.

 

[colordiamondfreak]

Hi David! I really appreciate your response. I like the stone, but if compared to a land-grown blue diamond I have seen prettier ones for much less. This one was very well priced if it could be proved to be all natural. If treated or lab-grown it was a terrible deal. I was so excited to think I might be able to afford a natural blue diamond, and maybe the gamble could have been worth it (I thought about never checking if it was natural or not and living life in a hopeful mystery) but I am too curious of a person. It wouldn't have worked.

Hi there. I'm so curious. How much was the stone priced at st the time when you saw it?