Does a large girdle variation affects the quality of the diamond?

[shinshino]

Hi all,

I am looking at a diamond with a large girdle variation from 0.8 to 2.4%.

Would this variation affect the quality of the diamond?
Also, is 0.8% consider too thin and risk chipping if set in an exposed ring?

thanks in advance.

 

[belle]

Date: 11/21/2005 1:21:08 PM
Author:shinshino
Hi all,

I am looking at a diamond with a large girdle variation from 0.8 to 2.4%.

Would this variation affect the quality of the diamond?
Also, is 0.8% consider too thin and risk chipping if set in an exposed ring?

thanks in advance.

that is not anywhere near a large variation of the girdle.
when stones are graded, the thinnest point and the thickest point are recorded. in this case, 0.8 and 2.4 are both considered ''thin'' so the girdle on this stone is ''thin'' all the way around without any large variation.
a thin girdle is not a problem set in a ring, unless the wearer is really hard on jewelry. in that case you may want to consider a bezel setting.

 

[Garry H (Cut Nut)]

Depending on the size of the stone, this stone may be near the border of thin and very thin and thick / slightly thick.

It might be (likely) 2-2.4% 90% of the way around the stone - and thinner at one point which can be set under a prong for protection against chipping while being worn.

Or the graduation could be uniform and therefore the stone would have a different symetry axis thru the corwn compared to the pavilion. This sounds worse than the optical affact - but would result in a symetry downgrade.

There is a chart here that might help
http://www.diamondcut.gia.edu/06_estimating_a_cut_grade.html

 

[shinshino]

Thanks belle and garry.

Is there any way to detect if it is the first or latter case?
like any data or scope view to detect it?

 

[valeria101]

Date: 11/22/2005 12:02:38 AM
Author: shinshino
Thanks belle and garry.

Is there any way to detect if it is the first or latter case?

Just looking at the girdle outline would be the easiest... A complete set of Sarin measurements would probably tell something too if you prefer.



like any data or scope view to detect it?

Ideal Scope or Aset or H&A viewer will tell if this has any weird effect (e.g. the girlde plane tilt Garry mentions).

Just my 0.2 on the matter... this is no worse than the usual buying scenario where cut quality needs to be assessed in person and someone has to see the stone (as opposed to a confusing listing in a database) for this. If you were going to have such evaluation done anyway, this girdle thing is just one more question to ask.

You could find another stone with even girdle measurements & without the ''problem. But... any number printed on a lab report is going to answer one question and pose 1000 more. As long as those are skimpy numbers that do not allow to practically ''reconstruct'' the stone fully, there are always questions and some educated guess if this or that is likely to be a problem etc.