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 Post subject: yellow diamond florescence
PostPosted: Thu Jun 28, 2012 12:37 pm 
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Would like to hear the experts opinions on how florescence affects the color of Fancy Yellow Diamonds.
Does is play a role in pricing?


Thanks,
360

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 Post subject: Re: yellow diamond florescence
PostPosted: Thu Jun 28, 2012 12:48 pm 
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360 wrote:
Would like to hear the experts opinions on how florescence affects the color of Fancy Yellow Diamonds.
Does is play a role in pricing?


not to my knowledge, but i would be very interested to hear other opinions......
ciao
alberto

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 Post subject: Re: yellow diamond florescence
PostPosted: Thu Jun 28, 2012 2:42 pm 
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very good question.
it depends on fluorescence effect,

if fluorescence makes stone hazy/milky its not good but generally the none Flu are slightly more expensive,

surprisingly other Fluorescence colors like Yellow/Green make stone cheaper.

of course i am talking about strong and very strong fluorescence

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 Post subject: Re: yellow diamond florescence
PostPosted: Thu Jun 28, 2012 3:38 pm 
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If clarity is the same, how do other factors affect Fancy Yellow Diamonds price? For example, How does thickness girdle affect the price? How does cut grade affect the price? by 10%? 30%?

Since the color is fancy yellow, does the cut grade affect the color, as in color stones?


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 Post subject: Re: yellow diamond florescence
PostPosted: Fri Jun 29, 2012 2:26 am 
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Moneyisnotmoney wrote:
If clarity is the same, how do other factors affect Fancy Yellow Diamonds price? For example, How does thickness girdle affect the price?

If girdle is too thick, it can make the entire stone look darker.
On the other hand, a thick girdle might actually enhance the face up color of a fancy color diamond. and can make the color more saturated, that is why most of colored diamonds are cut in fancy shapes other than round

Moneyisnotmoney wrote:
How does cut grade affect the price? by 10%? 30%?

that would be Symmetry and Cut Grading category, and of course lower the cut/symmetry would result cheaper price

Moneyisnotmoney wrote:
Since the color is fancy yellow, does the cut grade affect the color, as in color stones?

proportional and symmetrical cuts variation can have effect on the color because of windowing and extinction can result in weak or dark area of color in stone also it can have effect of evenness of the color which is include in the report

another good question would be how a cut decision can make a Y~Z colored diamond to a Fancy Light Yellow which i have opened the discussion here:
viewtopic.php?f=7&t=16063

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 Post subject: Re: yellow diamond florescence
PostPosted: Fri Jun 29, 2012 3:22 pm 
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Thanks Gents for all your help, especially the new thread!

After looking at a large batch of Yellow Diamonds, I found that florescence did not guarantee a milky or greenish tint. The cert does not always tell the entire story, but the eyes do. :)

360

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 Post subject: Re: yellow diamond florescence
PostPosted: Fri Jun 29, 2012 3:52 pm 
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360 wrote:
Thanks Gents for all your help, especially the new thread!

After looking at a large batch of Yellow Diamonds, I found that florescence did not guarantee a milky or greenish tint. The cert does not always tell the entire story, but the eyes do. :)

360

correct the eyes do not lie that's why to buy diamonds blindly only according the certificate one should see the stone in hand or trust an expert on the diamond who knows the right questions to be asked.

the certificates or to be more correct lab reports do not indicate many things, like metallic luster or milkiness or extra overtone colors also for brown tint diamonds before K color (we had the discussion here viewtopic.php?f=7&t=13541 )
still there are many other things and a lower cut quality does not always mean the stone is ugly (Old European cut is an example but there can be many other examples) or a stone with excellent cut grade can be not attractive enough as it should sound. this is why we still need experts and lab reports are not sufficient

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 Post subject: Re: yellow diamond florescence
PostPosted: Fri Jun 29, 2012 3:57 pm 
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Roshanravan - great insight on why buying online can be a pitfall!

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 Post subject: Re: yellow diamond florescence
PostPosted: Fri Jun 29, 2012 4:10 pm 
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we all know or at least have one or couple experience about shopping online, buying anything online can be pitfall and tricky,

i am very ethical regarding this issue, i sell diamonds to my customers without them seeing it and orders is not couple of hundreds it couple of thousands we are talking about, they just take my word because they know i do full disclosure, and i explain stuff they even do not know or would never notice it

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