GIA G/G = 0.7 on HCA?

[E B]

Since looking for a replacement diamond for my engagement ring, I''ve come across some interesting stones. One diamond''s (graded G/G by GIA) numbers looked interesting, so to see what would happen, I put it into the HCA....and it got a 0.7. EX/EX/EX/VG.

What''s up with that?

 

[Garry H (Cut Nut)]

GIA GG is for sym and polish. You have the other data - so what are the table crown and pavilion angles, and report # and ct weight please

 

[E B]

Date: 10/25/2006 4:09:55 PM
Author: Garry H (Cut Nut)
GIA GG is for sym and polish. You have the other data - so what are the table crown and pavilion angles, and report # and ct weight please

1.00ct

Depth- 60.8

Table- 54

Crown- 33.0

Pav- 40.8

Culet- None

 

[Garry H (Cut Nut)]

report # and ct wt alos please

 

[E B]

Gary,

The cert # is 15140802. I didn''t at all mean to imply that there''s a problem with the HCA, I was just surprised.

 

[Garry H (Cut Nut)]

Thanks ebree.

HCA tells you the optimum performance if the stone was perfectly symmetrical, polished and had no untoward tricks with minor facets (it only gets tabl, crown and pavilion main data).

This stone is suffering because of its Good Good for sym / pol - and has been downgraded because of that to Very Good Cut by GIA

If you run the proportions here http://www.facetware.gia.edu/ you will see that gIA also agrees the proportions are excellent

So there is no debate here

Here is all the data on your grading report:
Measurements: 6.46 - 6.54 x 3.95 mm

Carat Weight: 1.00

Color Grade: K

Clarity Grade: SI1

Cut Grade: Very Good

Proportions:

Depth: 60.8 %

Table: 54 %

Crown Angle: 33°

Crown Height: 14.5 %

Pavilion Angle: 40.8°

Pavilion Depth: 43.5 %

Star length: 55 %

Lower Half: 75 %

Girdle: Thin to Slightly Thick, Faceted

Culet: None

Finish:

Polish: Good

Symmetry: Good

Fluorescence: None

 

[E B]

Thanks, Gary! I''m not interested in the stone, I was just plugging numbers in- I haven''t and won''t buy a round without the HCA.