AGS grading system

[pelepup]

Hi,
I bought a diamond on ebay that had an old appraisal using the AGS numbering system. I did a quick search and found that AGS has upgraded the numbering system to correspond better with GIA. So how is it different than their old system? This appraisal is from 1979 and states that the color of the diamond is AGS-4, clarity is AGS-4 and cut is AGS-3. How does that relate to the current GIA scheme? Thanks for any help.

 

[69gm]

AGS equals GIA for color
0 D
0.5 E
1.0 F
1.5 G
2.0 H
2.5 I
3.0 J
3.5 K
4.0 L
4.5 M
5.0 N
5.5 O
etc. all the way to:
10 X,Y,Z

for clarity
0 FL/IF
1 VVS1
2 VVS2
3 VS1
4 VS2
5 SI1
6 SI2
7 I1
8 I2
9 I3

and you can go here for the cut:

http://www.diamondgrading.com/Articles_GIA_vs_AGS_CUT.htm

hope this helps.

 

[Mara]

69..if that is a recent chart, sounds like the original poster is saying that AGS used to have a different 0-10 system, I wonder if the info you posted STILL corresponds or would be different from 1979 AGS grading?

Possibly a member of the trade could pipe up?

 

[Richard Sherwood]

I think the clarity grading scale remained the same, as 69gm posted, while the color grading scale changed. A copy of the original scale is attached.

According to that, the stone was graded as an IJ color, VS2 clarity, with a good cut.

 

[pelepup]

Thanks everyone for the info! I'm going to get an official appraisal next week, but was wondering what the old appraisal meant. The old appraisal was apparently done with the stone already set so I expect that it will be off when I get the appraisal done with the stone removed and loose.

 

[69gm]

leave it to rich to save the day!

 

[Mara]

Thats an interesting picture, Rich. Note how colors D-I/J shows on the left side as 'mounted stones will appear colorless'. I like the 'tinted white' vs colorless/near/light yellwo etc..very interesting.

 

[Richard Sherwood]

It's out of an old book.