How much should I offer for 1.78 carat diamond studs, SI2, H color?

[lilmountaingirl]

So would you trust GIA reports for color and clarity, but not the cut specs? And trust AGS reports more, unless it is an older report before they become more strict?

I personally trust both GIA and AGS equally. They're both great labs in my opinion. Grading is subjective so even three graders from either lab might have differing opinions but they should still be in line with each other. The issue with GIA (in my opinion) is that their "excellent" cut grade covers a very wide range of parameters. So for instance there could be 1,000 diamonds that get graded as excellent but maybe only 150 of them are top tier performers. And AGS consistently gives their top cut grade to top tier performers. With GIA the category is too broad. It's like the SI grades, a very wide range of parameters. You can find SI1 diamonds that are not much more included than a VS2 or an SI2 that can be almost as included as an I1. It's too broad of a range to feel confident sometimes.

 

[DS2006]

I have had a hearts and arrows perfectly cut stone before that was GIA graded. But since the Excellent cut category is broad, you have to do more work to sort through and find the best ones. That starts with numbers for me, and then verified by light performance tools like and idealscope or ASET image. AGS Ideal cut does not mean you can buy blind, either, because I have seen some that I personally would not want. I think GIA is currently stricter on color on borderline color stones, and that affects price.

But as to age of the reports, if a stone has an old lab report (GIA or AGS), I would not trust in that alone. Diamonds do chip when worn or dropped, so you need a current evaluation on any diamond that has been previously owned. And I have used an independent, known diamond appraiser buying a second hand diamond, plus I had it regraded (he sent it for me).

 

[DS2006]

I find stones all the time with those specs, with girdle inscriptions from legit labs, for that price.

You are very lucky if you are finding AGS Ideal cuts and GIA Ex cuts (top ones) at 40%+ off retail! I have bought a few top cut stones second hand, but not at that much of a discount. I feel really happy if I find them at 20-25% off!

 

[nicole0612]

Very good info strengths and weaknesses of GIA vs AGS. Also an excellent point about age of the appraisal and possible chips to the stones in the meantime. I assume earrings would have less wear and tear than stones set in rings, but I am also thinking that if a stone has a very thin girdle or another feature that would be prone to chipping that I should be more wary about the potential damage over time.

 

[nicole0612]

So the seller got back to me with the paperwork, but she only provided the appraisal document, which means nothing. I have asked her to provide the original AGS grading reports that the diamonds were purchased with, and the sale being contingent on this. If she no longer has the reports, I will just let these go.

 

[ame]

Yea, that's a shame. I am suspicious that she doesn't have them.

 

[nicole0612]

Yea, that's a shame. I am suspicious that she doesn't have them.

Me too. She says that the appraiser is AGS certified, so I wonder if she just told me that they were graded by AGS because she didn't know the difference.

 

[ame]

Yea that's what I am thinking. Unfortunately there is a big difference.

 

[nicole0612]

Yea that's what I am thinking. Unfortunately there is a big difference.

Yes! Thanks for educating me!