Diamond calculation question

[karat]

Is there a way to figure the Star Length % from the information on an EGL certificate?

Is there a way to figure the lower half % from the same information?

I want to be able to run the GIA facetware software on some diamonds. I can get the angles for the crown and the pavilion by knowing the % values that are on the EGL certs if that can be used to get any of the above values.

 

[YoungPapa]

karat,

I''m afraid the answer is "no". I don''t think you can get the crown and pavilion angles from the percentages either, although some programs might give you an educated guess.

The real question you should be asking is if GIA Facetware can tell you what the color and clarity grades on an EGL diamond might be if the diamond were sent to GIA. Unfortunately the answer to that question is "no" as well...

 

[Corno]

I use a program at work, the name of which eludes me at this moment, but it can only create estimates based on standard practices or typical cuts. As most every stone, regardless of it''s cut, has it''s own nuances there simply is no program that can effectively determine the exact angles, sizes or percentages of the relating parts.

I use this program only as an estimate of potential weight based on the measurements of a mounted stone when removal of the stone is not desirable.

 

[Lorelei]

Date: 3/10/2009 9:37:18 PM
Author:karat
Is there a way to figure the Star Length % from the information on an EGL certificate?

Is there a way to figure the lower half % from the same information?

I want to be able to run the GIA facetware software on some diamonds. I can get the angles for the crown and the pavilion by knowing the % values that are on the EGL certs if that can be used to get any of the above values.

You might be better off getting an Idealscope or ASET image for the diamond.

 

[karat]

Thanks all for your reply.

I do use the cut advisor software on this site and the AGA grader software which gives some information on the type of cut. As you know there are a lot of shops that do not provide asset scope images even ones on this site. Due to the certs using the best cut angle on the diamond for the grading there probably is no way to tell from the dimensions given. I am beginning to feel you really need to look at the stone.

 

[Lorelei]

Date: 3/14/2009 12:37:36 PM
Author: karat
Thanks all for your reply.

I do use the cut advisor software on this site and the AGA grader software which gives some information on the type of cut. As you know there are a lot of shops that do not provide asset scope images even ones on this site. Due to the certs using the best cut angle on the diamond for the grading there probably is no way to tell from the dimensions given. I am beginning to feel you really need to look at the stone.

Indeed, or images of the actual diamond.