How do we Calculate Crown and Pavilian from a GIA report?

[Lysander74]

Hi

I have been show a GIA diamond with the following details. But on a GIA report the crown and pavillian is not given. I am trying to really figure out if this is a good diamond. Can someone help me out please. I am getting tired of looking for a good one.

Round Brilliant
Measurements: 6.28 by 6.37 X 3.79mm

Weight: 0.93
Portions
Depth: 59.9%
Table: thin
Gridle: thin to medium
Cutlet: none
Colour: F
Polish: Very Good
Symertry: Good
Cut: Very Good
SI1
Florescent: none

 

[Gypsy]

Can you post the report or a link to it?
If not if there is a Diagram on the cert with numbers on it, the C & P angles will be listed there.


ETA: Table cannot be thin. Should be a percentage, is that a typo?

 

[Regular Guy]

Lysander,

Welcome to Pricescope.

If the diamond is a little old, this data is not on the certificate, and cannot be derived from what is on it. But...if you have the certificate number, report check through GIA may find that data for you.

Do you have the report number, or know when it is dated from?

Unfortunately, though, the good symmetry is not a good start.

Don't give up. When you know what you want...even if you're committed to working with a local jeweler...tell them...by describing your criteria. They could become an agent working on your behalf.

eta...Gypsy may be right...that you're just missing it...if it does say cut is very good.

 

[Lysander74]

Hi

Sorry there was a typo the Table is 60%.

The diamond really sparkles. But I am just trying to figure out the crown and pavillian of the diamond. On GIA diamond reports they do not give this information.

Can anyone help me calculate it?

 

[Lorelei]

Welcome

You could ask the vendor to run a Sarin report on this rock which would give you the info. It seems that this diamond isn't cut to the tightest proportions, if you give us an idea of budget, perhaps we could offer some ideas? However if you have seen this diamond it might be an idea to compare it to others to see how it looks. Even mediocrity and poor cuts can look decent in jewellery store lighting, see if you can view it in other lights to see how it looks then.

 

[denverappraiser]

On the GIA reports that show a cut grade, there’s a little drawing of the profile of a diamond near the bottom right hand corner of the report that includes this information. Older reports don''t have this but they also don''t have the line item for cut grade. If you can''t find it, try posting a scan of the report and we''ll try to help.

Neil Beaty
GG(GIA) ICGA(AGS) NAJA
Professional Appraisals in Denver

 

[tanalasta]

Depending on when the report was done - you may be able to access the GIA report check service on their website.

If you enter your report number and carat weight (or post that here) you can check the information there.

The other alternative would be to ask someone to run a Sarin assessment on the diamond as that will give you the unrounded information on the crown angles.

After months of hair-splitting and researching diamonds on pricescope (and other sites) my take home message is that the maths isn''t as important as how the diamond actually looks in real life. You can analyse crown/pavillion angles to death, variations in star length and minor facets but they''re only a guide. The naked eye and visual aids (unless you have more technologically advanced ray tracing etc...) like the idealscope and ASET will tell you for sure if the diamond will truely ''shine''.

 

[Moikoi]

Date: 5/31/2007 6:50:22 PM
Author:Lysander74
Hi

I have been show a GIA diamond with the following details. But on a GIA report the crown and pavillian is not given. I am trying to really figure out if this is a good diamond. Can someone help me out please. I am getting tired of looking for a good one.

Round Brilliant
Measurements: 6.28 by 6.37 X 3.79mm

Weight: 0.93
Portions
Depth: 59.9%
Table: thin
Gridle: thin to medium
Cutlet: none
Colour: F
Polish: Very Good
Symertry: Good
Cut: Very Good
SI1
Florescent: none

maybe a little out of round? that''s way only a "good symmetry" grade?

this is a 60/60 stone....even to this day some old timer jewlers still swear they''re the best cut ever.