Clarity Question

[WinkHPD]

Date: 9/3/2007 4:06:36 AM
Author: Garry H (Cut Nut)
GIA wrote
Grade-determining clouds in the SI2 and I
clarity grades diminish the appearance of fire.
in http://lgdl.gia.edu/pdfs/cut_fall2004.pdf

Just avoid diamonds where there is a cloud mentioned and vendors say it is an otherwise exceptionally clean stone.

While I would agree with you in the SI2 and I1 catagories that have cliouds setting the grade, I will have to respectfully dissagree with you on the above comment. I have seen way too many stones with the "additional clouds not shown" comment that were talking about such tiny clouds of pinpoints with NO affect on light performance to ever agree with such a blanket statement. If you are referring to the lower grades, then yes, I agree, but your statement makes it look as if you are warning people to avoid all stones with such a comment, which would relegate WAY TOO MANY wonderful stones to the "unsaleables" catagory.

Wink

 

[WinkHPD]

Date: 9/2/2007 2:39:01 AM
Author: Gypsy
No. COLOR is graded from the bottom, the culet. CLARITY is graded from the table.

It''s not a grade thing, it''s a case by case thing. Like I said stones are graded for Clarity face up. So if what you want is a COMPLETELY eyeclean VS2 from all angles you need to have your jeweler, one you trust, look at the actual stone from all angles (or look yourself) and tell you what they see-- or don''t see as the case may be. Short of taking a HUGE cost increase of VVS grade, there is a chance that an individual stone below that grade might have inclusions visible from the side. So just be sure to explain what you are looking for. People on here have completely eye clean from all angles SI stones. It''s stone specific.


Also, the reason you can see an inclusion in the diamond from the side is that there is more transparency from the side... it''s more like a window... the table isn''t, it''s got all those angles and light shooting up. It''s also why with emerald cuts and asschers and other step cut stones it is difficult to find an ''eyeclean'' (even from the top) SI and sometimes even VS2. More transparency.
Good luck!

Gypsy, you state it very well. I had not even considered the clarity versus color grading since clarity was the only stated issue. I shall have to hope our supplicant was slightly confused and that our "jewelers" were not really giving him such erroneous information.

I might take slight dissagreement with the word transparency, as I think it not quite the correct word. I think the diamonds equally "transparent" from top to bottom or side to side, but from the top there is much more action in the form of both brilliance and more importantly scintillation that make the inclusions much more difficult to pick out because of so much "background noise".

Certainly I agree with you that it is much harder to get an eyeclean stone in an emerald cut, as the lack of activity in the background makes it much easier to see the inclusions.

Wink

 

[Gypsy]

Date: 9/3/2007 1:04:46 PM
Author: Wink

Date: 9/2/2007 2:39:01 AM

Author: Gypsy

No. COLOR is graded from the bottom, the culet. CLARITY is graded from the table.


It''s not a grade thing, it''s a case by case thing. Like I said stones are graded for Clarity face up. So if what you want is a COMPLETELY eyeclean VS2 from all angles you need to have your jeweler, one you trust, look at the actual stone from all angles (or look yourself) and tell you what they see-- or don''t see as the case may be. Short of taking a HUGE cost increase of VVS grade, there is a chance that an individual stone below that grade might have inclusions visible from the side. So just be sure to explain what you are looking for. People on here have completely eye clean from all angles SI stones. It''s stone specific.



Also, the reason you can see an inclusion in the diamond from the side is that there is more transparency from the side... it''s more like a window... the table isn''t, it''s got all those angles and light shooting up. It''s also why with emerald cuts and asschers and other step cut stones it is difficult to find an ''eyeclean'' (even from the top) SI and sometimes even VS2. More transparency.

Good luck!

Gypsy, you state it very well. I had not even considered the clarity versus color grading since clarity was the only stated issue. I shall have to hope our supplicant was slightly confused and that our ''jewelers'' were not really giving him such erroneous information.


I might take slight dissagreement with the word transparency, as I think it not quite the correct word. I think the diamonds equally ''transparent'' from top to bottom or side to side, but from the top there is much more action in the form of both brilliance and more importantly scintillation that make the inclusions much more difficult to pick out because of so much ''background noise''.


Certainly I agree with you that it is much harder to get an eyeclean stone in an emerald cut, as the lack of activity in the background makes it much easier to see the inclusions.


Wink

Thank you Wink, I''m glad to have the jist of my post affirmed... as to the word transparency-- it was the closest term I could find to what I wanted to say. What I really meant was ''noise'' as you''ve said. Thanks for the correction, as no doubt these posts will come up again, I will know the correct term to use.

 

[JohnQuixote]

Wink, I think I'm one of those who has described diamonds as having more transparency from the side with regard to clarity. This is only to imply that the facets work more as windows than mirrors in that orientation, so inclusions are less masked.

Regarding side-visible inclusions and grading, here is a past discussion which might be of interest.

 

[WinkHPD]

Well, you can be excused for using questionable terminology, after all, you were dealing with tricksy hobbitses in that discussion...

 

[WorkingHardforSmallRewards]

trans·par·ent (trāns-pâr'ənt, -pār'-) Pronunciation Key
adj.

1. Capable of transmitting light so that objects or images can be seen as if there were no intervening material.


AND

trans·par·ent /trænsˈpɛərənt, -ˈpær-/ Pronunciation Key - Show Spelled Pronunciation[trans-pair-uhnt, -par-] Pronunciation Key - Show IPA Pronunciation
–adjective

1. having the property of transmitting rays of light through its substance so that bodies situated beyond or behind can be distinctly seen.


I believe that per these definitions the reflective nature of an ideal cut round diamond from the face up view would prevent the diamond from technically being transparent face up. Definitions found at Dictionary.com

 

[Garry H (Cut Nut)]

Date: 9/3/2007 12:58:07 PM
Author: Wink

Date: 9/3/2007 4:06:36 AM
Author: Garry H (Cut Nut)
GIA wrote
Grade-determining clouds in the SI2 and I
clarity grades diminish the appearance of fire.
in http://lgdl.gia.edu/pdfs/cut_fall2004.pdf

Just avoid diamonds where there is a cloud mentioned and vendors say it is an otherwise exceptionally clean stone.

While I would agree with you in the SI2 and I1 catagories that have cliouds setting the grade, I will have to respectfully dissagree with you on the above comment. I have seen way too many stones with the ''additional clouds not shown'' comment that were talking about such tiny clouds of pinpoints with NO affect on light performance to ever agree with such a blanket statement. If you are referring to the lower grades, then yes, I agree, but your statement makes it look as if you are warning people to avoid all stones with such a comment, which would relegate WAY TOO MANY wonderful stones to the ''unsaleables'' catagory.

Wink

Thanks Wink
I should have qualified that "Clouds not shown" is a normal and frequent warning because it is impossible to represent a cloud on paper without over representing the cloud.
My other statements stay however. When the cloud is the grade maker I would never buy an SI stone and i would be very careful with a VS2 - if the cloud was near the culet it would be very bad.

Re the other topic about how easy it is to see inclusions in emerald cuts - -
1. Princess cuts have the same see thru effect for inclusions near the center of the table 9see pic)
2. The most frequent position of inclusions in princess cuts is this area - what would have been the dead center of the rough diamond. Please folks, check and comfirm. I think you will agree.

Therefore selecting princess cuts very much depends on the type of setting that will be used.
(this is one of my trade secrets)

 

[diagem]

Date: 9/3/2007 12:46:57 PM
Author: Wink

Date: 9/2/2007 1:59:43 AM
Author: vigorgs
I was told by several jewelers that they are graded from the bottom. Also, the jeweler in question explained he was GIA certified about 25 yrs ago and his instructor made it clear that VS2 and up should not be seen from the side or bottom. Although what you are saying makes sense.

I still have the question though, what grade should I go for to not have eye visible inclusions in a princess cut????

This is one of the big reasons why our industry is so poorly thought of by the public. Several jewelers telling you something so completely wrong can NOT be good for our reputation. It begs the question, were these real jewelers, or were they selling ladies shoes last week? Most mall jewelers are NOT real jewelers but sales clerks who should not be making up the information to fit their personal desire to bad mouth a stone you have already possibly purchased in order to try to sell you one of theirs.

Diamonds are to be clarity graded only from the top in setting the grade, although it is clearly easier to locate an inclusion from the side or bottom view and then turn it over to see if it is still visible. Many times I find tiny pinpoints in this manner, and then knowing that they are there I can find them from the top. Grading diamonds is part science, part art, and MUCH experience. Making stuff up is CRAP and inexcusable on the part of the people who do it and their bosses who let them. By the way, it is incredibly easier to grade a lower grade stone than a higher grade stone. The inclusions just jump out at you and you don''t have to search for the tiny pinpoints that would set the grade in a VVS or drop the grade in a potentially flawless gem.

This comment is incorrect, he may have been GIA educated, but he was NOT certified. If his instructor made it clear that VS2 and up were not visible to the eye from the side or bottom, then the instructor made it clear in direct contradiction to the written works of GIA since I was a student there in 1975. Did he do his work via correspondence, a one week or less class or in a residence class? Regardless of how he did it he obviously needs a refresher course to relearn the work correctly, as it was clearly presented differently in his written coursework, regardless of what his instructor might have said.

I just sold an I1 that would have fit your bill. It is not the grade, it is the stone. I have seen a 2 or 3ct GIA graded VS1 round with a clearly visiible from the top black pinpoint in the middle of the table. I even argued with GIA instructor about the grade and was told this was the only inclusion in the stone and it was a size that might have allowed the stone to pass as a VVS2 had it been clear instead of black. This was in a refresher class being taken at the Tucson Gem Show ten or twelve years ago and not one person in the class got that stone correct and we were all up in arms about it being a lucky grade.

Obviously you are entitled not to like this fact and to return the stone to the vendor and choose another one. If it is something that is only seen from two opposite sides and not from the other two sides then you can have it set so that the inclusion does not show, but if it is clearly visible from all four sides, then call your vendor and arrange for another stone to replace this one. Your vendor will work hard to find you what you want, and you may not have to go up in clarity at all, or you may have to, it partially depends on you. I have a client who for many years could see inclusions in VS2 stones from the top that neither I or his fiance/wife could see, and I AM good at it. Now, fifteen or twenty years later, his high tech job and the strain it put his eyes under have reduced that ability to a more normal acuity and he can comfortably buy VS2 and even SI1 stones

I wish you well in your quest, and I apologise on the behalf of my industry that you were fed so much excrementally convenient yet incorrect information by people who should have known better.

Wink

According to GIA maybe...
How would you set a grade on a VVS1/2? Only if you see it through the table?

Wink..., I said in a different thread..., GIA and other Labs must practice grading via a specific system to keep consistency...
I dont know any dealers/cutters/ or other pro''s in this business that grade or set the grades soley based on what they can see in the face-up position...


Another point..., I only partially agree with you its "incredibly easier" to grade an included vs cleaner Diamond...
Its true the inclusions easier to locate..., but you have "way" more parameters to consider when setting an accurate grade on an included Diamond!!!