would you buy a stone w/ an ''imperfect'' sarin?

[rkp2be]

...not that i''m looking at any right now, but i''m curious. how caught up should i get in the numbers? i know the numbers effectively make the diamond the dazzler or the frozen spit that it is, but i''m trying to figure out those stones w/ less than ideal numbers but great performance, IS images, etc. ..they exist, right?

for example: when i look at the HCA grid, over half of the area for an HCA "excellent" rating (i.e. red/dark orange space) is outside the GIA/AGS ideal candidate range. so what happens when a stone - let''s call him fred - is not classified "ideal" but scores great on HCA and has a great IS/ASET image. i''m assuming that this stone, fred, will probably not have all 0''s on the sarin (correct me if i''m wrong on this point..?). say i''m wanting to obtain an ideal cut stone, and i came across fred. do i pass because he''s not "ideal" on paper (i.e. paper stamped with "GIA" or "AGS")?

i know this issue is related to the industry''s push toward performance-based grading (see HCA''s explanation); i just want to understand it enough to be able to make the best diamond-buying decisions for myself...

ETA: add''l, possibly stupid, question - what do the zeros in the sarin mean? are they like the AGS grading where 0 is ideal, 1 is a step down, etc.? this is what i am assuming...

 

[Garry H (Cut Nut)]

Date: 3/20/2008 1:40:01 PM
Author:rkp2be

...not that i''m looking at any right now, but i''m curious. how caught up should i get in the numbers? i know the numbers effectively make the diamond the dazzler or the frozen spit that it is, but i''m trying to figure out those stones w/ less than ideal numbers but great performance, IS images, etc. ..they exist, right?

for example: when i look at the HCA grid, over half of the area for an HCA ''excellent'' rating (i.e. red/dark orange space) is outside the GIA/AGS ideal candidate range. so what happens when a stone - let''s call him fred - is not classified ''ideal'' but scores great on HCA and has a great IS/ASET image. i''m assuming that this stone, fred, will probably not have all 0''s on the sarin (correct me if i''m wrong on this point..?). say i''m wanting to obtain an ideal cut stone, and i came across fred. do i pass because he''s not ''ideal'' on paper (i.e. paper stamped with ''GIA'' or ''AGS'')?

i know this issue is related to the industry''s push toward performance-based grading (see HCA''s explanation); i just want to understand it enough to be able to make the best diamond-buying decisions for myself...

ETA: add''l, possibly stupid, question - what do the zeros in the sarin mean? are they like the AGS grading where 0 is ideal, 1 is a step down, etc.? this is what i am assuming...

You want an answer to the same thing as 1,000,000,000 others, so do I. IS is all I ever need for cut appearance. the numbers help with durability girdle thickness.

The ''0''s are the old AGS system from a few years ago - they mean nothing.

 

[strmrdr]

my 2c is that a diamond with a exellent IS image has VG(usualy EX) or better light return but good light return is not the whole story and it might not be well suited for the use you want too use it for or there may be other issues.

 

[rkp2be]

Thanks for the responses, very helpful (nice to know I''m not the only one!).

I''ve pretty much been relying on my own IS images combined w/ the numbers up to this point.... so do you think that - had I the option - it would not be necessary to have a sarin on a diamond I''m considering? More important would be a brilliancescope test or other performance test..?

Date: 3/20/2008 6:35:26 PM
Author: strmrdr
my 2c is that a diamond with a exellent IS image has VG(usualy EX) or better light return but good light return is not the whole story and it might not be well suited for the use you want too use it for or there may be other issues.

I ran into one of these with "other issues" recently - excellent IS image, great numbers (American ideal class 1B), but the stone just looked cloudy and not very sparkly/clear. It appeared to be due to tiny inclusions all around the outside edge reflecting all over. Quite disappointing, but an educational experience.