CBI vs ACA - Another pic and vid comparison

[blueMA]

Most PSers will defend their favorite vendors with their lives...

I myself am very vendor neutral. I judge each diamond for its merits without bias.
Based on seeing many helpful shopping posts I've seen, many others are as well.

 

[Lula]

@erislynn I'm very happy for you that you found a stone that you personally love. I'm in no way bashing CBI, and I along with most prosumers on this board would agree that CBI consistently source, cut and deliver one of the best quality diamonds in the world. However, CBI does not have some magic formula for cutting MRB that other vendors aren't aware/capable of.

And how exactly do you know this for a fact?

 

[blueMA]

And how exactly do you know this for a fact?

If you obsess over diamonds to learn everything about it, how do you not?

 

[blueMA]

Here's another video of my diamond studs - hard to focus indoors with an iPhone. It took me several months of hunt everywhere to attain these with their specific proportions, so I guess you may say I went a custom route. I absolutely adore my H&A engagement ring that unfortunately caused many women to stop wearing their rings around mine, but I wanted to try different proportions for earrings after a thorough research.

There's nothing wrong with being loyal to your specific vendor and trusting them to deliver consistent high quality diamonds, but there's absolutely no need to denigrate other vendors especially while there are factual variances among the available stones across the board.

 

[egemnoel]

The main difference *I* see is due to brand difference. I am not the only one to say so. Many PS’ers have chimed in supporting the fact that CBI has a consistent high contrast look. There are just as many 40.8 vs 40.7 pavillion angles with CBI as you see in the variances in ACA. It depends on when you’re looking at the inventory and what of the other 3 C’s you’re looking for.

Furthermore, I do not have to submit any kind of multi-stone proof. This is a testimonial. Do you have a brand vs brand multi-stone double-blind controlled study to show here? If not, your statement is opinion just like mine.

I have never said CBI is superior or better. I have stated the differences I observed, what I appreciated in each, and what my preference is. The bias toward ACA on this forum is ridiculous. As soon as there is a dissenting opinion, people swoop in and try to invalidate it. Makes one think if there really is no brand difference, why the defensiveness?

There is an easy explanation for what you read from CBI owners. If HPD were selling diamonds from multiple suppliers the reporting would be different. But they only use CBI.

Diamond producers have different processes. When going for light performance, brightness is relatively easy. That is just forcing some primary facets to certain angles. But nuances of dispersion, scintillation and contrast go beyond the outside facets, to virtual reflection strategies and 3D specifics not in any report or photo. Those nuances only get experienced in person.

Big factories do not get into such details. But the super-cutter producers do, and they have own goals and process. The nuance you experience all comes from the process. That makes for slightly different nuances between great performing diamonds. Not worse. Different. CBI has their own specific process. That is why the reporting is consistent. I read these threads and nod my head along with the other CBI owners. They are seeing what I see. Simple as that. No secret sauce. Just one team and they get it right every time.

If HPD started purchasing from multiple sources you would still see happy customers posting over the moon, as we do from the other great sellers here. They would also be able to list hundreds more diamonds. But they don’t do that. They chose to go with CBI only, for their own reasons (maybe because Wink does not want to sell a diamond that is just not up to his high standards ). They talk about that on the High Performance Diamonds website. Smaller inventory, I know, but Wink and his team love the consistency and so do I.

 

[blueMA]

No vendor sticks to an exact cookie cutter proportions when it comes to diamonds. However, they try to optimize the light performance as mentioned earlier.

I'm just sharing a copy/paste of the proportions I've noted from the CBI inventory while I was trying to search out my stones. As you can see, the pavillion angle varies from 40.7-40.9 and the visual differences from .1 change in the pavillion is huge.

CBI
56.8, 61.2, 34.2, 40.7, 55 77 - OP's
56.7, 61.3, 34.5, 40.9, 51 43.3, 77, tm
57.2, 60.9, 34.1, 40.8. 51 43.1, 78, tst
56.1, 61.9, 34.4, 40.8, 51 43.1, 77, tst
56.9, 61.4, 34.6, 40.8, 50 43.1, 77, tm
56.4, 61.5, 34.3, 40.8, 51 43.1, 77, tst
56.4, 61.7, 34.5, 40.8, 50 43.2, 76, tm

ACA
55.5, 61.2, 34.2, 40.7, 50 43, 76, tm
56, 61.4, 34.4, 40.8, 51 43.1, 77, tm
56.7, 61.3, 34.6, 40.8, 51 43.2, 76, tm
55.9, 61.9, 34.7, 40.8, 53 43.1, 76, tst
56, 61.7, 34.7, 40.7, 53 43, 76, tm
56.6, 61.6, 34.6, 40.7, 53 42.9, 78, tm
56.5, 61.5, 34.4, 40.7, 51 43, 77, tm

 

[Lula]

No vendor sticks to an exact cookie cutter proportions when it comes to diamonds. However, they try to optimize the light performance as mentioned earlier.

I'm just sharing a copy/paste of the proportions I've noted from the CBI inventory while I was trying to search out my stones. As you can see, the pavillion angle varies from 40.7-40.9 and the visual differences from .1 change in the pavillion is huge.

CBI
56.8, 61.2, 34.2, 40.7, 55 77 - OP's
56.7, 61.3, 34.5, 40.9, 51 43.3, 77, tm
57.2, 60.9, 34.1, 40.8. 51 43.1, 78, tst
56.1, 61.9, 34.4, 40.8, 51 43.1, 77, tst
56.9, 61.4, 34.6, 40.8, 50 43.1, 77, tm
56.4, 61.5, 34.3, 40.8, 51 43.1, 77, tst
56.4, 61.7, 34.5, 40.8, 50 43.2, 76, tm

ACA
55.5, 61.2, 34.2, 40.7, 50 43, 76, tm
56, 61.4, 34.4, 40.8, 51 43.1, 77, tm
56.7, 61.3, 34.6, 40.8, 51 43.2, 76, tm
55.9, 61.9, 34.7, 40.8, 53 43.1, 76, tst
56, 61.7, 34.7, 40.7, 53 43, 76, tm
56.6, 61.6, 34.6, 40.7, 53 42.9, 78, tm
56.5, 61.5, 34.4, 40.7, 51 43, 77, tm

BlueMA, you and the others who focus obsessively on the numbers and on the "cheat sheet" that is shared with every new poster are missing the point. What I'm saying, and what I believe the other CBI owners on this thread are saying, is that the numbers tell only part of the story. The numbers help narrow the field, so newbies can be reasonably sure that they are getting a well-performing diamond. But the numbers in and of themselves do not tell you about the diamond's cut precision. Cut precision makes a big difference in consistency in appearance and performance across stones from the same brand. I do not believe any of us on this thread are claiming that CBIs are "better" than other brands. What we are saying is that CBIs have a consistent appearance and performance across stones, which we find appealing. Threads from 2010 and earlier that address cut precision, cut consistency, optical symmetry, yaw, painting and digging, etc., helped me extend my understanding of diamond appearance and performance beyond a simple comparison of table, crown, and pavilion angles. In this way, I agree more with David (Rockdiamond) from DBL than I do with the posters who focus solely on the numbers. Shocking, I know!

 

[blueMA]

I do not believe any of us on this thread are claiming that CBIs are "better" than other brands.

Good agreed!

 

[egemnoel]

No vendor sticks to an exact cookie cutter proportions when it comes to diamonds. However, they try to optimize the light performance as mentioned earlier.

I'm just sharing a copy/paste of the proportions I've noted from the CBI inventory while I was trying to search out my stones. As you can see, the pavillion angle varies from 40.7-40.9 and the visual differences from .1 change in the pavillion is huge.

CBI
56.8, 61.2, 34.2, 40.7, 55 77 - OP's
56.7, 61.3, 34.5, 40.9, 51 43.3, 77, tm
57.2, 60.9, 34.1, 40.8. 51 43.1, 78, tst
56.1, 61.9, 34.4, 40.8, 51 43.1, 77, tst
56.9, 61.4, 34.6, 40.8, 50 43.1, 77, tm
56.4, 61.5, 34.3, 40.8, 51 43.1, 77, tst
56.4, 61.7, 34.5, 40.8, 50 43.2, 76, tm

ACA
55.5, 61.2, 34.2, 40.7, 50 43, 76, tm
56, 61.4, 34.4, 40.8, 51 43.1, 77, tm
56.7, 61.3, 34.6, 40.8, 51 43.2, 76, tm
55.9, 61.9, 34.7, 40.8, 53 43.1, 76, tst
56, 61.7, 34.7, 40.7, 53 43, 76, tm
56.6, 61.6, 34.6, 40.7, 53 42.9, 78, tm
56.5, 61.5, 34.4, 40.7, 51 43, 77, tm

I might not have been clear before. You can solve brightness neatly with external averages. But most of the numbers you posted stand for 8 separate measurements. Some of them stand for 16 and it actually would not matter if you knew all 57 measurements for each line, since it is only external facet data. You would have to un-average the averages, organise by facet groups, correlate XYZ lighting with each unique pairing and quartet and octet (and beyond) and work to recreate that specific diamond’s 3D virtual facet pattern that ultimately dictates the fine nuances of fire, scintillation and contrast.

I imagine you know there are people who believe any EX or Ideal diamond will be just as good as the next and the next. I absolutely do not believe that it is the case from my personal observations. I don’t know if you do. But I gather you believe a line of averages reveals everything about a diamond’s specific character. I totally disagree, but I respect your right to have that opinion. This is a place for dialogue, not censorship. I make my own testimonials, based on what I observe. So do you and if you were to come have a pint in Ireland and observe diamonds with me and you still felt differently that’s fine too. If we all felt the same way it would be a boring world!

 

[blueMA]

I imagine you know there are people who believe any EX or Ideal diamond will be just as good as the next and the next. I absolutely do not believe that it is the case from my personal observations.

Actually, this is absolutely the case. At a certain point, human eyes can't distinguish between one superideal diamond to another well cut similarly proportioned ideals, just as in clarity IF vs VS. I've absolutely seen this myself time and over IRL along with many others here on PS, and in fact most trade experts agree on this regard. In addition, peoples preferences for brightness/fire vary greatly, so what you personally prefer doesn't mean that's what others would want. I understand some want the "mind" assurance.

Just recently, I'm sure you've read this post?
https://www.pricescope.com/communit...between-wf-and-cbi.239329/page-3#post-4315090

I rest my case, since I see we're going in circles here.

 

[autumngems]

I'm too confused now, I have been searching for a stone and worried about HCA scores now I need to worry about skinny or fat arrows, ugghhhh

 

[Dancing Fire]

I'm too confused now, I have been searching for a stone and worried about HCA scores now I need to worry about skinny or fat arrows, ugghhhh

Look for stones with 76-77 LGF.

 

[Yang Kin]

I'm too confused now, I have been searching for a stone and worried about HCA scores now I need to worry about skinny or fat arrows, ugghhhh

Don't worry too much about HCA if you have the actual performance images, which are much more useful.