HCA question

[Beacon]

I am studying an attractive diamond listed on JA. Running all the numbers thru HCA it gets 1.9. Nice score. It is well within the HCA outlined area where a GIA excellent cut would be.

But the GIA cert on this gives it only a "very good". I ran the numbers thru GIA Facetware and also got "very good". Here are the numbers:

Table 57
CA 34.5
PA 41
Depth 61.7
Star 55
Lower half 85
no culet
Girdle Med-thick
8.98-9.07mm

The girdle having a top end "thick" is what separates this stone from "excellent" on GIA facetware. I think that the millimeters might be just a little small for carat weight of 2.80, but I might be wrong about that.

My question is: since HCA gives this stone a great score, would having a MED-THK girdle actually make it visually less appealing than an "excellent"? I know it''s a picky question, but that "very good" vs. "excellent" can mean a lot to the price on this 2.80ct stone.

Would this stone look bad?

 

[Ordieth]

Hello.

I am still a little new to all this, but I believe that the HCA is based upon a girdle of about 1.2% (thin to med). Since you are running with a medium to think, this is probably why it is graded differently than it''s score.

I can''t imagine a diamond with a "very good" score looking bad

, However, I couldn''t tell you for sure it''s affect on the apperance.

I hope this was a little helpful.

 

[Lorelei]

No the stone won't necessarily look bad at all! Is it possible to get a Sarin Report on this diamond as the numbers could be rounded? This would give a better idea and maybe an IS image? This diamond might be a real winner and if it was me, I would be wanting to check it out further for sure! I would prefer a different girdle measurement, but that wouldn't necessarily be a deal breaker if everything else was right.

I don't know if you have seen this thread on GIA rounding, but I will post it anyway as it might be useful.

https://www.pricescope.com/community/threads/consumer-advisory-gia-cut-grade-rounding-problems.39401/=

 

[Garry H (Cut Nut)]

Assuming the GIA proportion data is correct, then this diamond does not have a thick girdle - it probably has 1 small spot with a thick part as a result of a bit of creative cutting.

I see no reason why you would not ask for it to be sent to an appraiser for assessment if every thing else is OK.

It has a tiny bit of excess weight (.07ct) - but just under 3ct is very very hard to find in a decent cut

 

[Garry H (Cut Nut)]

BTW becasue of how AGS measure girdle compared to GIA - this is probably thin to medium on AGS''s scale

 

[Beacon]

Thanks to everyone for this information and explanation. I appreciate it!