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AGS 000 but HCA 3.1 Help??

Cutgirl

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I have seen a stone I really like with a AGS triple zero and great looking scan on the AGS cert. As a last minute thing, I plugged the numbers into HCA and it gets a 3.1! Was assuming it would be < 2. Should I go for another stone that I liked almost as much but it is a GIA XXX and ranks a HCA score of 1.2??? Thanks so much in advance.
 

luvdajules

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Hi OP, can you post the AGS cert? The scan on the cert is a computer model (mathematical model) not an actual ASET of the diamond. I've seen many pretty diamonds with a higher HCA, so don't fret. Also, provide budget and we can gauge what it should be priced at, a fair retail range, anyway. Many experienced vendors do not select in house diamonds with HCA as it's a calculation based off of only 4 discreet values (specs of a diamond); whereas a diamond is much more complex than that. However, HCA is a helpful tool for us consumers. Post again with more info so we can be of further assistance if you are in the choosing/selection process.
 

Niel

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No!

Don't get bogged down with overanalyzing. The HCA is NOT the end all be all. Use it along with other tools. But you're lucky. You found an AGS 000 (great) that has a nice idealscope (great) and you saw in person and loved (great!)

That trumps HCA score every time.
 

diamondseeker2006

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The ASET image on the cert is computer generated. I would not buy any stone with a 3+ HCA score without an actual idealscope image. There are some rare AGS "Ideal" stones with surprising leakage.

I'd want an image on the GIA stone as well. It could indeed be better.
 

Cutgirl

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Here is the scope copied from the AGS cert. Doesn't show a lot of leakage to me. I don't have a scan of the GIA one. Sorry

_435.png
 

SirGuy

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That's a computer-generated image, interpolated from the light performance mapping data. It looks like a real ASET because that's the basis of the real tool used. However, it's not an actual reflector image.

The AGS 0 grade is a great place to start, but it's not the end all. Ideal-Scope images, actual ASET images, and your own eyes do a good job as well.
 

Cutgirl

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I know the HCA can be a good selection tool but read it may leave out good ones. I am hoping I found one.
 

Texas Leaguer

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Cutgirl|1410891434|3751981 said:
I know the HCA can be a good selection tool but read it may leave out good ones. I am hoping I found one.
It's very possible that is exactly what you did Cutgirl.

SirGuy is correct, the ASET images you see there are computer generated. However, that is from a scan of the the diamond and the ray tracing analysis of every facet of the diamond, mathematically calculating the behaviour of 40,000 virtual light rays. So, if the scan was done correctly on a calibrated device (which the AGSL has alot of experience doing) then these images will be very close to any well done actual ASET photo. The images show great light return, very little leakage, and high optical precision (decent H&A patterning). These images combined with the fact that it is a Triple Zero indicates that it is a top performing diamond.

As others have said HCA is a good,easy to use tool for getting a rough idea of a diamond's potential, but takes into account a limited number of averaged and rounded measurements. The AGS analysis is much more sophisticated and gives you a much more specific picture of your diamond.

Assuming the diamond does not have other features that would diminish light performance, it should be a bright and beautiful rock. =)
 

diamondseeker2006

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I agree with Brian that the stone is likely just fine. But just to clarify, here is an AGS Ideal cut stone with a good ASET on the report, but the real idealscope and ASET show some slight leakage. This was my point as to why I don't rely on the AGS computer generated ASET.

http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3048657.htm?source=pricescope

I am thankful WF provides this information because it helps me determine which Expert Selection (AGS Ideal cut) stones would meet my standards (and many/most of them do!), although my preference is ACA's (top AGS ideal cut stones). The fact that they provide this information is exactly why I buy from them rather than buying from a vendor who provides no extra information. There is usually a cost differential to consider as well within the ideal cut range. I like to know what I am getting and am 100% certain I am getting what I am paying for, and I only buy from vendors such as WhiteFlash who are open and provide this information up front.
 

Niel

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I think we are ignoring some aspects of this post.

The OP said they saw it and compared it to other stones and preferred this stone best.

I think if you have an AGS 000 with a nice ,albeit computerized, aset and they also prefer how it looks best that's all you need. All the numbers in the world won't tell you which you prefer to look at most. And we know it's got a great cut so I don't see why the op cant jump on it.
 

diamondseeker2006

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Well, I can certainly see why it might be the best if that was the only AGS Ideal cut stone she was shown. If is is priced fairly (such as like WF expert selection or lower), then she certainly should buy it if she loves it. If it is priced like an ACA, I'd want proof that it performs like one because the report ASET doesn't look like it would make H&A. I totally get that not everyone cares to pay the premium for top cut quality. Just be sure the price is fair for what you're getting!

Cutgirl, if you want to know pricing for comparison purposes, if you could tell us the weight, color, and clarity, we can show you comps.
 

John P

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Cutgirl|1410887728|3751940 said:
I plugged the numbers into HCA and it gets a 3.1!
What are: Table%, Crown Angle?, Pavilion Angle?
 

Texas Leaguer

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diamondseeker2006|1410922808|3752290 said:
Well, I can certainly see why it might be the best if that was the only AGS Ideal cut stone she was shown. If is is priced fairly (such as like WF expert selection or lower), then she certainly should buy it if she loves it. If it is priced like an ACA, I'd want proof that it performs like one because the report ASET doesn't look like it would make H&A. I totally get that not everyone cares to pay the premium for top cut quality. Just be sure the price is fair for what you're getting!

Cutgirl, if you want to know pricing for comparison purposes, if you could tell us the weight, color, and clarity, we can show you comps.
DS, Good points all. Based upon the CG ASET this is not a super ideal, and if that is what Cutgirl is looking for she should consider other options. I just wanted to respond to the concern about the HCA score and as Neil said, the fact that she looked at it in person is confirmation. The other value factors are also very important and we do not have that info to work with.
 

Sunstorm

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OP, I was also going to say that if possible please post the specs, in particular percentages and angles. This you should have and we should know in order to be able to help you. They may or may not explain why you got a high HCA but without them it is not possible to fully assist you. If you want a super ideal, it is extremely important to have all this info and to compare stones. Yes, of course liking the stones and your eyes matter a lot too.
 

Cutgirl

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Thank you to you all! The low HCA is due to the angles: 59.3T, 60.8D, 33.1 Crown angle, 41.3 pavillion angle.
I do like nice cuts, but i will clarify that I don't need the top of the top. I appreciate everyone's comments.
 

Niel

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Cutgirl|1410997373|3752792 said:
Thank you to you all! The low HCA is due to the angles: 59.3T, 60.8D, 33.1 Crown angle, 41.3 pavillion angle.
I do like nice cuts, but i will clarify that I don't need the top of the top. I appreciate everyone's comments.
what were the numbers of the GIa stone you compared it to? It coudl be that your eyes prefer a 60/60 stone.
 

MelisendeDiamonds

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Cutgirl|1410997373|3752792 said:
Thank you to you all! The low HCA is due to the angles: 59.3T, 60.8D, 33.1 Crown angle, 41.3 pavillion angle.
I do like nice cuts, but i will clarify that I don't need the top of the top. I appreciate everyone's comments.

The HCA is telling you something as are that angle combination. Not all 59/61s have 33.1/41.3 CA/PA combination.
The comment you should have seen from the HCA output is something like "Worth Buying If The Price Is Right".

What are you alternatives for the same/similar specs and price?

Liking a bigger table and greater spread at the expense of other properties is a matter of taste, but even within those proportions there are better CA/PA combinations.

The real question is can better alternatives be bought for similar $$$, and this is something you will have to research a little more yourself if you want to make a more informed decision.
 

Cutgirl

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The AGS is a G/Si2 for 33,600. The other was a GIA X cut X symmetry, VG polish with 59t,59.7d, 32.5 crown and 40.8 Pav.
 

Cutgirl

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The GIA H is 34,800
 

Cutgirl

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Also, I got advice from another diamond dealer that an inclusion from pavilion to crown on the AGS might make it crack! Now, I am in mess!
 

Dee*Jay

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Cutgirl|1411059140|3753201 said:
Also, I got advice from another diamond dealer that an inclusion from pavilion to crown on the AGS might make it crack! Now, I am in mess!

It sounds like you got advice from a another "dealer" that is trying to sell you one of HIS/HER diamonds.
 

Cutgirl

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Dee Jay - I totally agree but I have it in my head. Won't buy from them though. THX. Voice of reason!!
 

Texas Leaguer

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Cutgirl|1411059140|3753201 said:
Also, I got advice from another diamond dealer that an inclusion from pavilion to crown on the AGS might make it crack! Now, I am in mess!
As i mentioned earlier, from a cut quality perspective you are OK based upon the information your have provided so far and your statement that you want a nice cut but not necessarily top,top cut. Now you have to consider other important value factors. The Si2 clarity is one that you have to take a very close look at. You would be best served here by laying out all the information you have available so that the prosumers here can help you break it down.
 

Cutgirl

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Sorry - here is the inclusion map of the AGS000

_22524.jpg
 

Texas Leaguer

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Cutgirl,
Best if you post the full cert. Other info contained on the report is quite relevant to understanding the nature of the clarity grade.

You also need to provide more info on the GIA stone if you want help in comparing the two options.
 

Cutgirl

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Here is the inclusion map for the GIA, H Si2 for 34,800. THX

inclusionshsi2.jpg
 

Cutgirl

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All the info!!
 

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luvdajules

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Hi OP, I don't download (paranoid about viruses), but given what I can see, I like what I see on the GIA one, the inclusion plot especially. Twinning wisps as the grade setting inclusion on an Si2 can be a lucky find if the wisps don't impede brilliance or transparency (appraiser can judge). I also like that the inclusions are mostly off to the side of the table, for the most part. I also like the length of the lgf, albeit GIA rounds up so may be longer in actuality.

I'm curious about your IRL experience in favoring the AGS0 stone, maybe it's the g color giving off slightly whiter flashes, or smaller splintery sparkle due to a longer lfg than the GIA? If I downloaded the files I could see if one is benefiting from fluoro or not. On paper, I would have thought the GIA would have been the favored, but the eyes like what they like. Anyway, would you like us to look to see if there are other stones to compare or consider? I'm guessing around a 2 to 2.5 ct. Hope you get more help soon, I'll be watching your thread with interest :wavey: Either way, I'm certain you will get a phenomenal stone that you will love!
 

Texas Leaguer

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Looking at the certs I am not surprised that you preferred the look of the AGS diamond. The gemological specs are extremely similar but the nature of the inclusions in the GIA stone would indicate more of a likelihood that light performance would be diminished. If your eye told you that, there would be no reason not to take the lower color for the higher price. The potential durability issue of the feather would not concern me very much, although you should have either stone examined by an independent third party gemologist with real credentials.
 

Cutgirl

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Texas Leaguer - your comments have been exceptionally helpful!
 
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