Please help with Sarin- which is more accurate?

[Milo]

Hello- I am looking at possibly purchasing this AGS diamond. When I plug the numbers from the AGS cert into the HCA , it rates as a 1.0 however when I use the numbers from the Sarin report received, the HCA rates 2.2.... how can the same diamond get such a different rating rating when comparing cert with sarin? Which is more accurate? Also I am attaching the Sarin info received. Can anyone advise on how I should read this, my head hurts. I also received this picture. Since it is over 2, is that a bad thing. Should I keep looking? Thanks all.

 

[Milo]

sarin info

 

[Milo]

Let''s try to load up the sarin again....

 

[stone-cold11]

AGS info is more accurate. Sarin, or any other precision instrument, needs to be calibrate often and use correctly. Who do you think depends more on the accuracies of their instrument for their brand?

Just get an idealscope image, if there is no leakage, HCA score of about 2 is not a concern.

 

[Dreamer_D]

Ask for an IS image, it trumps the HCA anyways.

 

[Todd Gray]

I''m unable to see the Sarin file Milo, you might consider posting the following information from both the AGS lab report and the Sarin:

Measurements: (diameter and depth)
Total depth: %
Table diameter %
Crown angle: degrees (not the percent which is height)
Pavilion angle: degrees
Girdle thickness:
Culet size:

A little bit of clarification... The last time I checked, both the GIA and AGS laboratories use Sarin technology... I have a lab quality Sarin machine on my desk and it self-calibrates - so there is no need for me to calibrate it, nor is there an option to mess with the calibration. That said, a little variation in readings exists not only between the machines, but also within the same machine each time a diamond is measured - but they are a whole lot more accurate than trying to eye ball a stone! There are less expensive units designed primarily for a retail counter top "oooh isn''t it shiny!" type of sales presentation which are far less accurate - so I guess the performance of the machine depends on the model.

There have been times when I''ve been in the process of evaluating a diamond and I find myself staring at the measurements published on the lab report and those appearing on my screen and wondering "what the?!?!" to the extent that I called Fred Fish at Sarin NYC and once he explained to me that the variance could be due to the lab tech using the wrong lens option to measure the diamond (there are different lenses and platforms for different sizes) to which I responded "G-R-E-A-T" and he said "it happens". Of course, the possibility of the wrong lens and platform configuration can be achieved on both sides of the equation, both in the lab and in the sellers office - so... why not ask for a new Sarin?

 

[Lorelei]

Date: 4/7/2010 4:08:34 PM
Author:Milo
Hello- I am looking at possibly purchasing this AGS diamond. When I plug the numbers from the AGS cert into the HCA , it rates as a 1.0 however when I use the numbers from the Sarin report received, the HCA rates 2.2.... how can the same diamond get such a different rating rating when comparing cert with sarin? Which is more accurate? Also I am attaching the Sarin info received. Can anyone advise on how I should read this, my head hurts. I also received this picture. Since it is over 2, is that a bad thing. Should I keep looking? Thanks all.

Hi Milo

It is usual to see some variance between report numbers and Sarin, AGS are the numbers of authority so go by those, Sarin can sometimes be inaccurate for various reasons. The diamond has potential in the photo, if you could post all the numbers from the report here and request an Idealscope image of the stone, then we can go from there.

 

[Milo]

Thank you all for your replies so far. For some reason, the Sarin report won''t load so I will write out the info that was suggested for any thoughts that you may have. Just to reiterate- the AGS info comes back at 1.0 on the HCA and the Sarin report comes in at 2.2- also if someone can comment on the white part at 6 oclock in the diamond pic that I posted and whether that would be a concern- I refer to the star shape in the centre that is all black except for the part at 6 o''clock. I will leave this to the experts and thanks again!

CERT INFO AGS
Measurements: 7.67 X 7.69 X 4.75
Total depth: % 61.8
Table diameter % 56.2
Crown angle: degrees 35.2
Pavilion angle: degrees 40.6
Girdle thickness: 1.7 -3.8%
Culet size: pointed


SARIN INFO (I have copied this exactly from the report that I received...girdle part seems a little weird)
Diameter 7.67 (7.63-7.69)
Depth: 4.74
Total depth: % 61.8
Table diameter % 56.3
Crown angle: degrees 35.3
Pavilion angle: degrees 40.8
Girdle thickness: 1.8% 1.4% medium 02.6% Sl. thick 0 0
Culet size: 0.5%

 

[Todd Gray]

Date: 4/7/2010 7:29:08 PM
Author: Milo
Thank you all for your replies so far. For some reason, the Sarin report won''t load so I will write out the info that was suggested for any thoughts that you may have. Just to reiterate- the AGS info comes back at 1.0 on the HCA and the Sarin report comes in at 2.2- also if someone can comment on the white part at 6 oclock in the diamond pic that I posted and whether that would be a concern- I refer to the star shape in the centre that is all black except for the part at 6 o''clock. I will leave this to the experts and thanks again!

CERT INFO AGS

Measurements: 7.67 X 7.69 X 4.75
Total depth: % 61.8
Table diameter % 56.2
Crown angle: degrees 35.2
Pavilion angle: degrees 40.6
Girdle thickness: 1.7 -3.8%
Culet size: pointed

SARIN INFO (I have copied this exactly from the report that I received...girdle part seems a little weird)
Diameter 7.67 (7.63-7.69)
Depth: 4.74
Total depth: % 61.8
Table diameter % 56.3
Crown angle: degrees 35.3
Pavilion angle: degrees 40.8
Girdle thickness: 1.8% 1.4% medium 02.6% Sl. thick 0 0
Culet size: 0.5%

All right, there is some variance in the Sarin, but it''s actually not as far off as you might think, it''s "within tolerance" and more than likely is due to a difference in the accuracy of the different models of Sarin available.

As for the one arrow in the six o''clock region being white while the others are black (as they should be) it might be as simple as the stone being tilted a little while it was being photographed, but it could also be due to a variance in the facet structure of the diamond - in which case, personally, I would request a 3D version of the Sarin file and a manufacturers report which will show the facet-to-facet structure of the diamond and enable you (or one of us with experience) to determine how the stone "flows"...

 

[Lorelei]

Date: 4/9/2010 4:46:15 PM
Author: Todd Gray

Date: 4/7/2010 7:29:08 PM
Author: Milo
Thank you all for your replies so far. For some reason, the Sarin report won''t load so I will write out the info that was suggested for any thoughts that you may have. Just to reiterate- the AGS info comes back at 1.0 on the HCA and the Sarin report comes in at 2.2- also if someone can comment on the white part at 6 oclock in the diamond pic that I posted and whether that would be a concern- I refer to the star shape in the centre that is all black except for the part at 6 o''clock. I will leave this to the experts and thanks again!

CERT INFO AGS

Measurements: 7.67 X 7.69 X 4.75
Total depth: % 61.8
Table diameter % 56.2
Crown angle: degrees 35.2
Pavilion angle: degrees 40.6
Girdle thickness: 1.7 -3.8%
Culet size: pointed

SARIN INFO (I have copied this exactly from the report that I received...girdle part seems a little weird)
Diameter 7.67 (7.63-7.69)
Depth: 4.74
Total depth: % 61.8
Table diameter % 56.3
Crown angle: degrees 35.3
Pavilion angle: degrees 40.8
Girdle thickness: 1.8% 1.4% medium 02.6% Sl. thick 0 0
Culet size: 0.5%

All right, there is some variance in the Sarin, but it''s actually not as far off as you might think, it''s ''within tolerance'' and more than likely is due to a difference in the accuracy of the different models of Sarin available.

As for the one arrow in the six o''clock region being white while the others are black (as they should be) it might be as simple as the stone being tilted a little while it was being photographed, but it could also be due to a variance in the facet structure of the diamond - in which case, personally, I would request a 3D version of the Sarin file and a manufacturers report which will show the facet-to-facet structure of the diamond and enable you (or one of us with experience) to determine how the stone ''flows''...

Ditto, also post the IS image when you get it then we can go from there.