How to know if GIA XXX or AGS000

[parkour]

How can you tell if a diamond is GIA XXX or AGS000 given
Table 57
Crown 33.5
Pavilion 40.8

It seems to be right at the border.

 

[lovedogs]

Well that stone appears to be certified by GIA, so whether or not its a GIA XXX is just by looking at the report. Did you plug the numbers into the HCA?

I think it's on the border due to being somewhat shallow.

 

[lovedogs]

Edit. There's not enough info posted to calculated HCA. Need ct weight and mm size.

 

[bmfang]

How can you tell if a diamond is GIA XXX or AGS000 given
Table 57
Crown 33.5
Pavilion 40.8

It seems to be right at the border.

If you are talking about AGS 0 Ideal on proportions, then this one likely is that and GIA XXX.

However, if you want to know whether it scores AGS000 for light performance, symmetry and polish (which results in an AGS0 cut grade based on light performance), that is something that you cannot readily tell from GIA proportions given that they are heavily rounded.

 

[the_mother_thing]

GIA XXX means the GIA report notes the diamond to have ‘Excellent’ Cut, Symmetry & Polish, I believe. It looks like you have the GIA report, so just see what it notes for those items. The only way to know for certain if it’d score AGS ideal grading is to send it to them.

I think all the charts, HCA, etc. are helpful to narrow down a search and/or let you know you might be in the range of GIA XXX or Ideal, but only an independent lab report can really tell you for sure.

 

[parkour]

Edit. There's not enough info posted to calculated HCA. Need ct weight and mm size.

6.22 - 6.27 x 3.81 mm
0.91 ct
I checked HCA is 0.9

 

[lovedogs]

6.22 - 6.27 x 3.81 mm
0.91 ct
I checked HCA is 0.9

Ok. That's good, and means the angles are complimentary. But I don't know for sure about it being on the edge of ideal, etc. Again my guess is bc it's shallow (ish). Do you have any advanced images like ASET/IS?

 

[bmfang]

Likely angle combo on this stone is 33.6/33.7 for CA coupled with 40.75/40.8 for pavilion.

This has got fairly good spread.

Can the vendor provide you with any images of the stone as well as scope images?

 

[Dancing Fire]

If your GF throw the ring back at your face then you'll know it is not a AGS 000. JK, I had a few tonight.