Question about GIA cert

[locke]

Hello,

I was wondering if I should be concerned about the comments on the GIA cert for a diamond I am interested in. There are two comments, one which says "clouds are not shown" and another which says "surface graining is not shown". Could the clouds have something to do with the fact that the diamond has faint fluorescence? I uploaded the diagram here. I''m looking on bluenile so I can''t see for myself, but I''d like to know if I should be worried about these comments and/or the inclusions shown on the attached before I commit to buying. I could always order it and see but I''d like to avoid the hassle of a return if possible.

Thanks in advance.

 

[locke]

Okay I just did a search on surface graining and came up with about 1,000 topics. Sorry about that. My question about additional clouds still stands though if anyone can help.

 

[JohnQuixote]

Date: 3/19/2007 7:59:18 PM
Author:locke
Hello,

I was wondering if I should be concerned about the comments on the GIA cert for a diamond I am interested in. There are two comments, one which says 'clouds are not shown' and another which says 'surface graining is not shown'. Could the clouds have something to do with the fact that the diamond has faint fluorescence? I uploaded the diagram here. I'm looking on bluenile so I can't see for myself, but I'd like to know if I should be worried about these comments and/or the inclusions shown on the attached before I commit to buying. I could always order it and see but I'd like to avoid the hassle of a return if possible.

Thanks in advance.

Hi Locke,

Inclusions "not shown" on a document from a strong lab like GIA typically means they are non-factors, particularly with SI1 and higher clarity. See this thread for discussion on the same question (7th post down talks about clouds). Clouds are collections of microscopic pinpoints, or clarity characteristics unrelated to fluorescence. Faint fluorescence as judged by GIA is not enough to influence the look of the stone in common lighting situations.

 

[locke]

Thanks John. I love when I get the answer I am hoping for.

 

[EdSkinner]

If there are clouds running through the stone there is a chance you can get yellow fluorescence.

 

[DiamondExpert]

Sorry, perhaps I missed something...what do clouds have to do with fluorescence?

 

[EdSkinner]

When I am appraising a stone and I get faint yellow fluorescence the first thing I look for is a cloud going through the stone and usually there is. Don''t know what causes it, maybe the impurities in the pin points.

 

[DiamondExpert]

Interesting anecdote - how many observations like this have you made? I think yellow fluorescence is thought to be associated with a particular arrangement (lens-like) of clustered nitrogen atoms in the diamond crystal - but your observations bring up the interesting question of whether or not there is a, perhaps not causal but coincidental, common occurrence of clouds in stones stones with yellow fluorescence...

I''ve not heard of such an observational connection between these two properties before, but it would be of interest if others here might have...anyone?

Also, do all stones with yellow fluorescence appear cloudy, and do all cloudy stones have yellow fluor?

Yellow fluor isn''t that common, so it might be difficult to get the numbers necessary to do a meaningful study - except at the major grading labs.

...GIA probably already has the answer (except that they are/have been pretty lax in noting/characterizing fluor on their certs).

 

[Richard Sherwood]

Date: 3/22/2007 2:32:16 PM
Author: Basset Hound
When I am appraising a stone and I get faint yellow fluorescence the first thing I look for is a cloud going through the stone and usually there is. Don''t know what causes it, maybe the impurities in the pin points.

I''ve noticed this a lot as well with stones that have yellow or greenish yellow fluorescence. They tend to have more clouds than usually seen. It''s come up enough times that it''s definitely gotten my attention and piqued my curiosity.

 

[Richard Sherwood]

Locke, the phenomenan we''re talking about probably has nothing to do with your stone. If it is notated "clouds not shown", it means they are a "non-factor" in the clarity grading of the stone, as John pointed out.

I personally don''t care for the word "cloud" to describe these groupings of pinpoints. The word "cloud" gives the impression that the stone could be cloudy, when this is usually (99.9% of the time) not the case.

 

[EdSkinner]

Date: 3/22/2007 7:23:45 PM
Author: DiamondExpert
Interesting anecdote - how many observations like this have you made? I think yellow fluorescence is thought to be associated with a particular arrangement (lens-like) of clustered nitrogen atoms in the diamond crystal - but your observations bring up the interesting question of whether or not there is a, perhaps not causal but coincidental, common occurrence of clouds in stones stones with yellow fluorescence...

I''ve not heard of such an observational connection between these two properties before, but it would be of interest if others here might have...anyone?

Also, do all stones with yellow fluorescence appear cloudy, and do all cloudy stones have yellow fluor?

Yellow fluor isn''t that common, so it might be difficult to get the numbers necessary to do a meaningful study - except at the major grading labs.

...GIA probably already has the answer (except that they are/have been pretty lax in noting/characterizing fluor on their certs).

I can not document how many times I have seen this phenomenom over the years, but have seen enough that if I see faint yellow flourescence I look for a cloud. Not all yellow fluorescence means that there is a cloud through the stone, but to me it sets off a red flag and is something that should be looked for. I think that yellow fluorescence is much more common than what you believe. It is the second most common color of fluorescence next to blue. Now to get back to the person who started this thread: Locke, just because a stone has a cloud and faint fluorescence does not make the stone bad. Worry when the fluorescence is so intense that it makes the stone foggy and a cloud when it makes the stone kind of translucent. If GIA gave this stone a SI1 believe it. Because GIA means God In America. They can not possibly be wrong.