need help deciding on a diamond and HCA questions

[jin866]

Hi,

I would really appreciate your help on understanding the following cut parameters and decide which one is a better one:
stone 1) 2.26ct
table 57.1%
deepth 61.0%
crown 34.2 (33.9-34.4)
pavil 41.9 (40.8-41.2)
culet 1.4%-2.0%

symmetry EX polish EX
HCA 1.6 (EX VG VG VG) --- HCA score is good, but why 3 VG? I saw another stone score HCA 3 with 4VGS

stone 2) 2.52ct
table 56%
depth 60.8%
crown 35.2
pavilion 40.4
girdle 0.7%-1.5%

symmetry VG polish EX
HCA 0.6 (EX EX EX VG)

Question: Which one should I chose? I was more comfortable with stone1 ''s parameters as it seems to be similar to other well cut H&A stones. But I don''t want to miss out stone 2 if it is a super performer.
So which crown & pavil comb produces better results? I remember seeing some tutorial on GOG on bad performers with <1 HCA stone, want to make sure stone 2 is not one of those.

Another questions: What is LGF and star people talking about on other posts? Are they related with the performance of the stone?


Thanks so much for your kind help.

Jin

 

[Garry H (Cut Nut)]

If I were buying for stock on the info so far, and if there is not a big price diff i would take the 2.5ct.
I am sure it would measure a lot bigger.

Can you get ideal-scope photo''s

if not i would have that stne shipped to an appraiser.

The shallower pavilion (40.4) is compensated by the steeper crown angle.
The girdle is thinnish though and if you are a brick layer then it is too thin. 6 or 8 prongs - not 4, for protection

 

[strmrdr]

I dont care for the second one if the crown was 36.2 then I would be kewl with a 40.4 but 35.2 is a bit shallow for it in a ring.
It would make a kicken pendant.

An IS image would be nice to see what the LGF and stars look like.

LGF and stars are talked about here:
http://www.goodoldgold.com/minor_facets.htm

 

[jin866]

Thanks so much Gary and Stmrdr. No they don''t have idealscope image.
The concerns I had for stone2 was the thin girdle and the steep/shallow combination that was talked about in some previous threds. So stmrdr you do think this 2.52 will run into the steep/shallow + HCA<1 issue?

A concern I have on stone1 is the 41 pavilion. I know 40.6-40.8 is ideal. But how bad is 41 pavilion? Is 41 still be in AGS0 in the new grading? Will stone 1 be GIA excellent?

It is so hard to have everything. Thanks so much for the comments.

Nana

 

[jin866]

Again if pavilion 41 is a definite no-no ( I will be unhappy, I will regret ... ) I can forget about it. But if it is an ok choice, then I intent to have the diamond checked by an appraise. I love stone2''s size, just have the above two concerns. But if you expert feel those are not problems, then I will rethink about stone2.

Thanks so much,
Nana

 

[strmrdr]

pavil 41.9 (40.8-41.2) <--- there has to be a typo here...

If the average is 40.9 that means most of the facets are under 41.
A heart&arrows picture or an IS image would help a lot.
Or a 3d sarin scan.

The other one is one of the problem combos that Garry likes and a lot of people dont in a ring.

 

[Garry H (Cut Nut)]

I would seriously suggest you have that 2.5ct examined.
It is within the zig zags of the AGS candidates and if the lower and upper girdle facets are OK, and the girdle has only one thin spot to pop under a prong then you will have a stone that will look far better than the stones you are being advised to consider when it is dirty (ie all the time).

 

[jin866]

Hmmm, interesting. It was 41.0 pavilion.

Thanks very much,
Nana