Opinions needed on some rocks

[DiamondDealHunter]

Here are some of the standouts I found on Pricescope that fit my specs and budget. Also, are the size differences noticeable if they were next to eachother. Thanks
1.12
G
SI1
60.8%
56%
AGS
thn-st
no
id
id
no
6.72-6.66-4.07
$4731 / CT
$5299
--------------------------------
1.06
F
SI1
62.2%
56%
AGS
med-st
no
ex
ex
no
6.56-6.51-4.07
$5060 / CT
$5364
----------------------------------
1.15
G
SI2
61.6%
55%
AGS
thn-me
no
id
id
no
6.77-6.73-4.16
$4158
$4781
--------------------------------
1.08
F
SI2
60.9%
56%
GIA
thn-me
no
vg
vg
no
6.66x6.64x4.05
$4256
--------------------------------
I would love to get an H&A but not sure if any of these qualify. If anyone has any better suggestions, please let me know.

Thanks
Sergio
$4596

 

[Garry H (Cut Nut)]

Get crown and pavilion aangles for 1st and last stones and plug into cut adviser.

 

[Rhino]

I'd ditto that. Not only would you want that data but whenever I see "SI" I always think to myself ... where's the inclusions, what type are they, are they eye visible or not? There are so many variables unanswered there that it's hard to make a recommendation. Even if it score great on the HCA what if you're picking with with a big ol shiner under the table? Is this a local place that you can go to to view the diamonds or if on the net do they provide pictures taken under darkfield illumination?

Peace,
Rhino

 

[Garry H (Cut Nut)]

Hey Rhino,
Ever stopped to think about dark feild illumination?
Why does every one in USA use it?
What you see in darkfeild has little bearing on what you 'see'.

It is one of the funniest dumbest GIA inventions of all time.

Dark feild is for finding features that we use to identify natural / synthetic with colored gemstones

Noone in the trade outside gIA trained people use Microscopes for other than VVS diamonds. As you know most educated buyers do not buy VVS (see Rapaport 20 year price comparisons to know why).

The illumination that should be used with SI stones is normal frontal illumination blocked by on observers head

10X magnification is rather silly too - 2X would be more than adequate, then if you can see it with the unaided eye - pass

 

[DiamondDealHunter]

Hey Cut Nut....teach me something, why did you choose those two stones? I am going to have to make some calls to get the other numbers, I was afraid that would be my answer.

Thanks

 

[Garry H (Cut Nut)]

OK. But then we gotta kill ya

 

[Rhino]

haha..

Hey buddy!

One reason why I would ONLY use darkfield illumination in the analysis of clarity is because of the contrast it casts upon the imperfections within the stone making it easier for the gemologist (and layman) to find under magnification and to make the more important seperations between the clarities.

While I agree with your points concerning overhead illumination and what it shows and the 2x vs 10x magnification, I would NEVER make a clarity judgement based on 2x mag with overhead light. Not when we're talking the kind of money we spend. For some people it may be fine but not for me personally. I have to admit though ... we'd probably sel a helluva lot more stones.

Peace,
Rhino

 

[RockDoc]

----------------
On 1/25/2003 2:42:42 AM Cut Nut wrote:

Hey Rhino,
Ever stopped to think about dark feild illumination?
Why does every one in USA use it?
What you see in darkfeild has little bearing on what you 'see'.

It is one of the funniest dumbest GIA inventions of all time.

Dark feild is for finding features that we use to identify natural / synthetic with colored gemstones

Noone in the trade outside gIA trained people use Microscopes for other than VVS diamonds. As you know most educated buyers do not buy VVS (see Rapaport 20 year price comparisons to know why).

The illumination that should be used with SI stones is normal frontal illumination blocked by on observers head

10X magnification is rather silly too - 2X would be more than adequate, then if you can see it with the unaided eye - pass

----------------

2x examination for clarity????????? This makes no sense when trying to separate a flawless stone from a VVS one. Graders should use whatever power they need to find the inclusion then go back to 10x.

How about grading large stones where a really minute inclusion could be more visible in comparison to a small stone?

Dark Field illumination is not an invention of the GIA. Dark Field is used for many scientific analysis projects.

Frontal lighting? Reflected light to search for inclusions? GIA scopes can quickly be converted to total backlight light with the flip of a switch. In addition, the GIA scope can be used with the lights off, and using a auxiliary type of illumination of the examiner's choice.

The GIA standards, while they've changed, have been basically in use since the 1930's.

Your suggestions seem to indicate that you wish to establish your own standards that appear to fly in the face of the GIA's standards, or for that matter any industry standards.

Why don't you "cooperate" with the standards already set by GIA, until such time that the standards are changed. Certainly GIA would welcome intensely scientifically researched suggestions for change, if such changes had academic proof of their accuracy.

Rockdoc