Very thin girdle a nono?
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belle
Super_Ideal_Rock
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edited to be cautious of extremely __ to extremely ___ anything. a girdle is not going to be *perfectly* even all the way around, but you don't want to have it grossly uneven, especially to the extreme. even a very thin girdle could be questionable.
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The way these things are graded always leads me to want to "look" at each diamond. I would avoid "extreme" things most of the time, but maybe this is a tiny area of the girdle. It might be an entire side or two, but it could be just at a pointed end. It might be easily altered, or maybe the stone should be skipped. One needs to have a look-see to be sure.
One thing is the average girdle thickness, the way it is presently done is we take the extremes, regardless of their quantity, and the mid-point word is their "average girdle". This is a ridiculous system, but it is the one in use. If a diamond had a tiny thin spot and was nearly all thick otherwise the "average" would be reported as "medium" when truly the stone overall or on average is "thick". If one were to measure 8 places on the girdle and 7 were thick and 1 was thin, how could the "average" really be "medium"? But, that is how it is presently being done. This is not the way it will be in the future, but for now, we abide with the system as it is.
An extremely thin area will remain an issue of durability regardless of size, but if located in a fortunate place, it might be rectified very easily.
One thing is the average girdle thickness, the way it is presently done is we take the extremes, regardless of their quantity, and the mid-point word is their "average girdle". This is a ridiculous system, but it is the one in use. If a diamond had a tiny thin spot and was nearly all thick otherwise the "average" would be reported as "medium" when truly the stone overall or on average is "thick". If one were to measure 8 places on the girdle and 7 were thick and 1 was thin, how could the "average" really be "medium"? But, that is how it is presently being done. This is not the way it will be in the future, but for now, we abide with the system as it is.
An extremely thin area will remain an issue of durability regardless of size, but if located in a fortunate place, it might be rectified very easily.
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Having an extremely thin girdle means that that part of the diamond could chip very easily upon impact. Especially in diamonds that have pointed edges like a Princess cut and Emerald cut. It is more from a structural integrity issue ie durability of the diamond, hence is a big NO-NO.
However, it might be all right if it is covered by a prong but I'm not 100% sure. I've had a X-thin girdle on my old EC (already traded-in) that was fortunately located where it could be protected by a prong and I never had any problems for over 10 years. That said, I did not wear the ring often and took it off for most activities and when at home.
An extremely thick girdle just means that the diamond is hiding some carat weight in the girdle and will appear smaller than it should.
However, it might be all right if it is covered by a prong but I'm not 100% sure. I've had a X-thin girdle on my old EC (already traded-in) that was fortunately located where it could be protected by a prong and I never had any problems for over 10 years. That said, I did not wear the ring often and took it off for most activities and when at home.
An extremely thick girdle just means that the diamond is hiding some carat weight in the girdle and will appear smaller than it should.
belle
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david,
you said that an extremely thin girdle could mean that just one side or even one small area was "extremely thin", but where do the averages that you were talking about come in with the extremes? let''s use your example of just one side being extremely thin, and the rest thick, what does this equal? thin? i know the grading system isn''t good as it is now, i''m just trying to understand how on average, there is an "extreme" if it is not mostly that way.
you said that an extremely thin girdle could mean that just one side or even one small area was "extremely thin", but where do the averages that you were talking about come in with the extremes? let''s use your example of just one side being extremely thin, and the rest thick, what does this equal? thin? i know the grading system isn''t good as it is now, i''m just trying to understand how on average, there is an "extreme" if it is not mostly that way.
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Done the way it is presently done, a diamond with Ext thin to Ext thick would average as "Medium".
The same would happen with a stone having a V thin to V thick that would average "Medium", too.
Thin to Thick would also average "Medium"
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The problem is we are talking about the extremes, not points measured several times around the girdle being averaged. If 1 part of a girdle is graded Ext thin and 7 were actually Ext thick, we presently would get "Medium" from most labs,,,,,and that is a wrong-headed, illogical way to do the job. The same would hold true if 1 part was Ext thick and 7 parts was Ext thin. Still "Medium".....It means nearly nothing done this way.
However, because we can''t see the diamond, we warn people to avoid all stones with Ext thin girdles yet we really don''t have a clue as to how much or how little of the stone is actually fragile. We can and will do better very soon.
The same would happen with a stone having a V thin to V thick that would average "Medium", too.
Thin to Thick would also average "Medium"
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The problem is we are talking about the extremes, not points measured several times around the girdle being averaged. If 1 part of a girdle is graded Ext thin and 7 were actually Ext thick, we presently would get "Medium" from most labs,,,,,and that is a wrong-headed, illogical way to do the job. The same would hold true if 1 part was Ext thick and 7 parts was Ext thin. Still "Medium".....It means nearly nothing done this way.
However, because we can''t see the diamond, we warn people to avoid all stones with Ext thin girdles yet we really don''t have a clue as to how much or how little of the stone is actually fragile. We can and will do better very soon.
JohnQuixote
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Good overview, Dave.
In short, that description of the girdle is not enough to go by. Have someone look at it if you are interested and then remember that the most important thing with relation to this (or any princess for that matter) is proper care by the setter who will set the stone.
The issue of princess cuts and girdle breakage was discussed at length in an interesting thread linked here.
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You just have to marvel ate the skill of these guys who can get the very most out of each piece of rough.
somone will buy this stone already set in a ring - probably a 4 claw - and it will probably have a perfectly happy life.
It will have been cut from an octahedra - imaging 2 pyramids joined at their base.
karenleah15
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Beach
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any half decent setter would place a prong over that area and it would be quite safe Pyramid.
I admire your annoying persistence
I admire your annoying persistence
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That is an actual 3D scan from a Sarin owned by one of my suppliers. I can model the suppliers stones in DiamCalc and see what it will look like thru the ideal-scope etc - and run DiamCalc light return and contrast on it.
I can also send the file to anyone who can download a free version of Gem Adviser and they can do the same.
I can also send the file to anyone who can download a free version of Gem Adviser and they can do the same.
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Actually i am just off a 10 hour red eye flight from Hong Kong with narry a wink''s sleep.
I would not buy a stone like this myself - more for the symetry defects and very thick girdle.
It is about a 1ct stone from memory - and the girdle part shown is the thinnest - it would grade as Very Thin me thinks
I would not buy a stone like this myself - more for the symetry defects and very thick girdle.
It is about a 1ct stone from memory - and the girdle part shown is the thinnest - it would grade as Very Thin me thinks
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