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To cut or not to cut? Very light green to Fancy Green

BloomsburyHouse

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I posted a while back on what to do with a 1.29ct very light green OMB.

Somebody on PS highlighted the possibility of having the diamond re-cut to improve the colour. I contacted the extremely helpful Paul Slegers at Infinity Diamonds in Antwerp at the suggestion of another PS member and having assessed the diamond here's what he says:

"We have closely examined your stone, and here is our assessment. The question mark is the Strong fluorescence on the stone, as it adds a layer of unpredictability to the final stone.

As far as the current stone goes, the original cutter has basically approached the stone in every incorrect way possible. Good thing is that this leaves room for colour-improvement, but that it goes together with serious weight-loss.

With a final weight between 1.00 and 1.05, the colour can be improved to Fancy Green, but I must remind you about the ‘unpredictable’ factor of the fluorescence"


I have to decide what to do. To cut or not to cut! Here is the link to the current GIA report

http://www.gia.edu/cs/Satellite?pagename=GST%2FDispatcher&childpagename=GIA%2FPage%2FReportCheck&c=Page&cid=1355954554547&reportno=2151843038

If anyone has any views on what the fluorescence might do or the potential increase in value of the stone I'd be really keen to hear from you!
 

BloomsburyHouse

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I have photos but there are not very good as the colour balance is off20131211_113055.jpg20131211_113228.jpg20131211_113048.jpg

The stone looks way more saturated than in real life. It's in Antwerp right now.
 

iota15

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I'm sure you know much better than I would. I'm just interested in seeing where you take this stone.

I thought fluorescence though, only shows up in certain lighting. Wouldn't it still be good to have it fancy green most of the time?

We generally tell people the fluorescence won't affect the colour that much, and even if it did, only in certain lights. Thus, girls shouldn't expect their J colour stones to magically look like a G with strong blue fluorescence.

I have no idea how it would affect a fancy green stone. Were you planning to sell it after the recut? I believe GIA grades stones in labs that don't really "turn on" the fluorescence (not until they get to the test where they are checking for it anyway). Let me know if I'm wrong.
 

tyty333

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How much diameter would you lose in the recut? A fancy green would be a lot more valuable than a very light green...but I
understand that its a bit of a crap shoot.
 

pinkjewel

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If it was yellow fluorescence I don't think I'd like it as much. But since it's blue fluor I'm thinking that in certain lights it would give a really pretty bluish green effect. I've seen a couple of greens on Leibish's site which had blue fluor and the effect was lovely. I know in my fancy pink oval with strong blue fluor- I love the effect. Do you notice any of the fluor now in your diamond? I hope someone more knowledgeable about cutting chimes in. If it were me, depending on how much I paid for the diamond to begin with, if I thought the cutter was an excellent cutter for fancy colored diamonds- I would do it-even considering the weight loss. You would gain much more value in a 1 carat fancy green (and wouldn't it be cool if you got a fancy bluish green color) than your present light green. Just wondering what the estimated cost of recutting it is?
 

kenny

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You commented that you are not happy with the color balance of your pics.
I'd be happy to attempt to color-correct them and post them with your permission.
If your answer is yes, then I must ask if the paper the diamond is on is white.

I'm confused about the fluorescence thing.
The GIA report dated Jan 15, 2014 says medium blue fluorescence, but Paul says strong fluorescence.
Did he make that comment before seeing the GIA report?

When it comes to value, at least blue is one of the better hues for a green diamond.
A Bluish-Green grade would be much better for the valuation than a yellowish green. (ETA, as Pinkjewel just mentioned)
It really depends how much UV is in the light that GIA uses to graded colored diamonds … but then they already graded it using that light and they didn't call it Bluish Green, just green … but who knows … maybe a recut (which makes the light bounce around back and forth more times before finally exiting out the top, will cause the light to pick up not only green body color but blue color from the fluorescence.



Very Light Green to Fancy Green is a MASSIVE jump … THREE GIA grades of improvement! :-o :-o :-o .
I am astonished this much improvement is possible, though I'm certainly not challenging Paul.

If I owned the stone I'd get it recut but first attempt to get the opinion of the Graduate Gemologist and FCD expert Shumlik Polnauer at Leibish at www.fancycoloreddiamonds.net
He attends the Argyle Tender auctions and makes the call on which to bid on and has made the call to recut some which subsequently got higher color grades from GIA.
I have no idea if he will offer his expertise on stones not handled by his company, but perhaps he could provide additional contacts.

You could also look up Stephen C. Hofer the FCD expert in MA.
He wrote that 9-pound Bible of the colored diamond field.
http://www.amazon.com/Collecting-Classifying-Coloured-Diamonds-Illustrated/dp/0965941019

Here's a video of him discussing this topic. https://www.youtube.com/watch?v=9LJBgZ_gZoI

gia_color_7.jpg
 

RockyRacoon

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kenny|1393027330|3620402 said:
I'm confused about the fluorescence thing.
The GIA report dated Jan 15, 2014 says medium blue fluorescence, but Paul says strong fluorescence.
Did he make that comment before seeing the GIA report?

GIA is notoriously bad for their fluorescence grade. I've seen stones that were graded Medium appear Very Strong and stones rated Faint appear Medium, closer to Strong.

There just seems to be a lot of inconsistency with the benchmarks for fluor.

I hope that both GIA and AGS eventually provide more insight into fluor, as I purchase many stones based on this detail alone!
 

kenny

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RockyRacoon|1393028126|3620406 said:
kenny|1393027330|3620402 said:
I'm confused about the fluorescence thing.
The GIA report dated Jan 15, 2014 says medium blue fluorescence, but Paul says strong fluorescence.
Did he make that comment before seeing the GIA report?

GIA is notoriously bad for their fluorescence grade. I've seen stones that were graded Medium appear Very Strong and stones rated Faint appear Medium, closer to Strong.

There just seems to be a lot of inconsistency with the benchmarks for fluor.

I hope that both GIA and AGS eventually provide more insight into fluor, as I purchase many stones based on this detail alone!

Perhaps because the exact wavelength of UV light (or the strength at various wavelengths) varies with the choice of the UV light bulb, and how old the bulb is.
Different bulb = different results.
Same bulb new or old = different results.

Just guessing here.

And how exactly are the grades, faint … medium, strong, very strong, defined?
Does everyone use the same criteria?
 

RockyRacoon

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kenny|1393028315|3620407 said:
RockyRacoon|1393028126|3620406 said:
kenny|1393027330|3620402 said:
I'm confused about the fluorescence thing.
The GIA report dated Jan 15, 2014 says medium blue fluorescence, but Paul says strong fluorescence.
Did he make that comment before seeing the GIA report?

GIA is notoriously bad for their fluorescence grade. I've seen stones that were graded Medium appear Very Strong and stones rated Faint appear Medium, closer to Strong.

There just seems to be a lot of inconsistency with the benchmarks for fluor.

I hope that both GIA and AGS eventually provide more insight into fluor, as I purchase many stones based on this detail alone!

Perhaps because the exact wavelength of UV light (or the strength at various wavelengths) varies with the choice of the light bulb.
Different bulb = different results.

Just guessing here.

Seems like a very smart guess!

Hopefully they codify the lighting at some point, so there can be a universal benchmark (or at least a general baseline) for fluor.

Now it would be REALLY awesome if they decided to include phosphorescence color/level as an additional detail, but that might be asking a bit much!
 

yssie

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RockyRacoon|1393028551|3620409 said:
kenny|1393028315|3620407 said:
RockyRacoon|1393028126|3620406 said:
kenny|1393027330|3620402 said:
I'm confused about the fluorescence thing.
The GIA report dated Jan 15, 2014 says medium blue fluorescence, but Paul says strong fluorescence.
Did he make that comment before seeing the GIA report?

GIA is notoriously bad for their fluorescence grade. I've seen stones that were graded Medium appear Very Strong and stones rated Faint appear Medium, closer to Strong.

There just seems to be a lot of inconsistency with the benchmarks for fluor.

I hope that both GIA and AGS eventually provide more insight into fluor, as I purchase many stones based on this detail alone!

Perhaps because the exact wavelength of UV light (or the strength at various wavelengths) varies with the choice of the light bulb.
Different bulb = different results.

Just guessing here.

Seems like a very smart guess!

Hopefully they codify the lighting at some point, so there can be a universal benchmark (or at least a general baseline) for fluor.

Now it would be REALLY awesome if they decided to include phosphorescence color/level as an additional detail, but that might be asking a bit much!

I am confident GIA graders pull fluor grades out of hats. Reputable vendors have echoed the sentiment that they are notoriously inconsistent.

The two small endstones don't have reports.
GIA reports on *both* middle sidestones state fluor to be "none".
One of the large sidestones has "faint" fluor per GIA, and the other has "none", also per GIA.
365nm UV (advertised, so probably closer to 380 IRL)



Whatever they use - old bulbs, new bulbs, red bulbs, blue bulbs - they need to standardise it and the interpretation of it!

fluor.png
 

BloomsburyHouse

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Sorry guys I'm on GMT so was fast asleep during most of the activity!

Kenny - I'd be delighted for you to re-balance the pictures - thank you.

I had contacted Leibish before but they were not interested.

I'm not sure I understand the 'unpredictability' of the fluorescence. Paul seems to imply that the fluorescence might negate any effect of the cutting. I didn't send him the GIA report, it is his assessment that it is strong.

I wonder if any knows what the stone is worth now (1.29ct very light green) compared to if it gets re-cut (1ct fancy green)?

Yes I'd like to sell it but I've never sold something like this before so I don't know what the market is like.

Thanks
 

distracts

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I don't think any of us can really make this decision for you since there's no guaranteed outcome... but I have to say I really dislike the cut of the stone as it is, and even if the color wasn't improved by a recut, I think the eye-appeal certainly would be. Since I personally would not wear the stone as it is now, I would be willing to take even the risk of the stone being destroyed or coming out half the size.
 
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