7.4mm CBI or 7.68mm GIA Ideal ?

[Coconutpalm]

For the same price

7.4mm x 7.4mm CBI
SI2 (Completely eye clean)
H




Or

7.68mm x7.68mm
Si1 (Eye clean)
H
GIA Ideal
HCA = 0.9 (Excellent Light Return, Fire, and Scintillation)

 

[Dancing Fire]

CBI, if eye clean..The second one is not a H&A stone.

 

[Matthews1127]

For the same price

7.4mm x 7.4mm CBI
SI2 (Completely eye clean)
H




Or

7.68mm x7.68mm
Si1 (Eye clean)
H
GIA Ideal
HCA = 0.9 (Excellent Light Return, Fire, and Scintillation)

Stone #1 HCA:

Both have similar appeal, but you should see how each performs in different light environments. Can you get videos of each diamond?

 

[gm89uk]

If you have a good refund policy, buy the GIA stone and take instore to compare at a CBI location near you.

There is no right answer, the size difference should be noticeable, although not large. You might find the increase in light performance is not as important as the size difference or vice versa.

 

[HappyNewLife]

I'd go CBI!

 

[valeria101]

The SI2 seems to have subtler marks than the SI1, this once...

I am finding barely anything to think about: a little diameter, subtle IS details not aparent in the ASET (of the GIA XXX) - versus an impecable H&A pedigree (IHMO, it is nice to have 'the best' of something!).

Rationally, would roll the dice !

2c

Yes, it is nice to line such things up & let them 'soeak to you', as they say. The last bit of magic that I cannot imagine done virtually, yet ...

 

[metall]

If you have a good refund policy, buy the GIA stone and take instore to compare at a CBI location near you.

There is no right answer, the size difference should be noticeable, although not large. You might find the increase in light performance is not as important as the size difference or vice versa.

I think that this is the best suggestion! You really do need to see a comparison side by side to really know what YOUR eyes can tolerate, and what you think of the stones in person.

 

[OoohShiny]

This. ^^^

 

[bmfang]

No such thing as a GIA Ideal, only GIA excellent that has Ideal specs (just me being nit picky).

Having said that, comes down to whether you want super ideal precision or you can live with a little bit of assymetry in your stone. An approximately 0.3mm difference in diameter is likely to be noticeable and that could be the defining factor over something smaller that is more precision cut.

gm89uk’s suggestion is the best way forward if you can afford to do so (and assuming you have a CBI dealer close by).

 

[diamondseeker2006]

This is tough. Obviously a CBI diamond is beautifully cut and desirable. But I just wouldn’t personally consider SI2 clarity for an engagement ring. The cut of the other one looks fine. Even though it’s SI1, I question whether it’s eyeclean. Please post the actual images of the stones.

Do you think size is important to the recipient? If it is, I will tell you that there is a visual difference between 7.4 and 7.68. If you think she’s expecting smaller than 7.4, then she might be fine with the smaller one. But I’d still switch to a CBI with higher clarity.

 

[simon123]

I spoke to the CBI team last year about SI graded stones. Paul and Lieve reject about 100 SI2 possibilities for every one we go forward to craft and then, of course, the lab gives some of those SI1. CBI challenge them back down to SI2 but the lab doesn’t budge in certain cases. So the CBI SI2 is a wonderful rarity that appears to the naked eye every bit as clean and sparkly as a VVS or Flawless diamond at a fraction of the price. Use the ‘See it to believe it’ and see for yourself. Only you can be the best judge. Good luck in your search.

 

[mrs-b]

The GIA stone. I like a larger stone, and its stats are excellent. I'd check to make sure it's eye clean - but then I wouldn't hesitate. Just because it isn't a CBI stone, doesn't mean it isn't exceptionally beautiful. Its stats are terrific, and WELL above normal. So I agree with diamondseeker2006 - if your girl is interested in size at ALL, then I'd go GIA; its arrow pattern is very clean and strong, and those heads are nicely aligned.

 

[rockysalamander]

CBI for me.

 

[Tourmaline]

I voted CBI before I looked at your post. Now I am unsure, because I don't like the ASET on the CBI, and SI2 without any major inclusions is not going to be very bright. But I don't like the inclusion in the GIA Ideal, either. So, for me, it would be neither of these.

 

[OoohShiny]

I voted CBI before I looked at your post. Now I am unsure, because I don't like the ASET on the CBI, and SI2 without any major inclusions is not going to be very bright. But I don't like the inclusion in the GIA Ideal, either. So, for me, it would be neither of these.

May I ask the reasoning for this?

Is it an assumption that the grade-setting inclusion(s) are clouds or twinning wisps that are scattering/absorbing light? (We'd need to know the AGS certificate so we could review the plot diagram, unless I've missed it in the thread.)

I know that vendors can't comment on or promote individual stones but @Paul-Antwerp or @John Pollard or @Wink might be able to comment on CBI's policies on inclusions and their effects on performance - I know they are hyper-focused on light performance so I have doubts that they'd allow poor-performing SI2s through the net!

 

[LLJsmom]

If no chance to compare IRL, CBI. If possible see both and then decide.

 

[yssie]

I know that Infinity specifically plans cutting for light return around inclusions. Because of this, I wouldn't evaluate the possibility of inclusions affecting light return in a CBI SI2 in the same ways that I would a generic SI2. Whether or not the stone is eye clean to your personal preferences is a different question - be sure to ask about inclusion visibility at 6" face-up and 20deg tilt if that's your requirement as it might differ from their default definition.

The GIA looks like a lovely stone. It's not H&A, but you aren't paying for H&A... the CBI is, as you know, cream of the cut crop! Agree with @diamondseeker2006 - the size difference will be noticeable IRL if you have both stones side by side; it may or may not be memorable when you've got only one in front of you.

What country do you live in? This seems like the perfect opportunity to take advantage of CBI's SITBI policy, if available to you:
https://www.hpdiamonds.com/en-us/diamonds/diamonds-home

 

[diamondseeker2006]

I spoke to the CBI team last year about SI graded stones. Paul and Lieve reject about 100 SI2 possibilities for every one we go forward to craft and then, of course, the lab gives some of those SI1. CBI challenge them back down to SI2 but the lab doesn’t budge in certain cases. So the CBI SI2 is a wonderful rarity that appears to the naked eye every bit as clean and sparkly as a VVS or Flawless diamond at a fraction of the price. Use the ‘See it to believe it’ and see for yourself. Only you can be the best judge. Good luck in your search.

This makes zero sense to me. Why would any diamond cutter challenge a clarity grade because they want it lower???

 

[yssie]

This makes zero sense to me. Why would any diamond cutter challenge a clarity grade because they want it lower???

Ditto. Huh?

 

[John P]

I spoke to the CBI team last year about SI graded stones. Paul and Lieve reject about 100 SI2 possibilities for every one we go forward to craft and then, of course, the lab gives some of those SI1. CBI challenge them back down to SI2 but the lab doesn’t budge in certain cases.

This makes zero sense to me. Why would any diamond cutter challenge a clarity grade because they want it lower???

It's actually correct. In fact it's an excerpt from an email reply I sent on the topic a while back.

First, for anyone wondering what "recheck" is: After a producer submits a parcel of diamonds for grading the lab returns an email with preliminary results. At that time, for an extra charge, you can request 'rechecks' of grades you believe they missed. The lab conducts those rechecks, and either confirms you’re right and changes the grade, or reports there was no change.

With that understood, @diamondseeker2006 and @yssie, you're right. Challenging down is unique. Labs are rarely asked to lower grades. It's a tough business and diamond producers typically accept 'upgrades' and run with them. We don't. Why? Quixotic morals aside it’s all about brand protection. Our professional retailers are super smart and picky. When they ask for an F we're going to deliver an F - not a G or H with a ‘lucky cert.' This empowers them to increase their orders, sight-unseen, with full confidence we have this covered at the production and lab-submission level.

You are familiar with policing for ‘eye-clean,’ which a number of great PS retailers do for consumers. This is the same concept, just farther upstream. We're enforcing standards to provide confidence for our fellow professionals, as well as their consumer clients.

 

[LLJsmom]

This makes zero sense to me. Why would any diamond cutter challenge a clarity grade because they want it lower???

Would they do this to reinforce their stance on their level of integrity? If they don't think a stone is correctly evaluated, even if it's on the high side, they will challenge to see if there was an error? I can understand and appreciate that, although I am sure it rarely happens among vendors.

 

[diamondseeker2006]

@John Pollard Very interesting! So basically CBI will guarantee the AGS color grade would be equal to GIA color grading? That would be a big selling point.

 

[yssie]

Interesting insight, thanks for clarifying @John Pollard!

On the one hand... I’m thinking “how lovely to find such an upstanding vendor!!”
On the other, though, I’d be lying if I didn’t say part of me winced.

I will say that my field is one wherein anything and everything can and will be used against you, so not taking advantage of a lucky break would be... inadvisable. I can’t claim to know your pipeline at all, so I guess I’ll just say that I hope that the supply chain with which you deal so honestly is (and remains!) as just in its dealings with you

 

[Coconutpalm]

I want to sincerely thank everyone for their great advice and insight. I am still debating between the two and finally got a chance to see them in person (not side by side, unfortunately). As you all know in my original post, I stated that both diamonds were the same price, however I was mistaken and the GIA is $700 more expensive than the CBI. Also, I'd like to include the clarity plots for both diamonds for you all to see (again, they are both eye clean):

GIA:


CBI:


I am in the process of procuring videos, so will update you all by end of the week. Keep the comments coming

 

[SimoneDi]

OP, I think that you have received some great advice here. I will chime in and state the following;
1. An appx 0.3mm difference in noticeable and if your SO is interested in “size”, I would consider the difference.
2. As someone who has an SI2 diamond, I am very accepting of lower clarity grades, however, I really don’t love the crystal table inclusions. I see them in the ASET image and I see them on the diamond plot.
3. $700 is not a significant difference, but if you tell Yekutiel that $700 is the deal breaker, I am likely to think that he may be willing to make an exception.

In the end, both choices seem to be lovely diamonds regardless of their shortcomings and I think that your fiancé-to-be will be thrilled with either one!

 

[John P]

@John Pollard Very interesting! So basically CBI will guarantee the AGS color grade would be equal to GIA color grading?

No way. All labs make mistakes. And rechecks are not always successful, in any case. We recheck grades at any lab, both up and down, based on our knowledge. As intimately acquainted as we are with each diamond, our authority regarding our product is more consistent than any outside organization could be.

For context, GIA grades around 40,000 diamonds per week across nine locations. In the worst moments they're off from our assessments by up to 2 grades in both directions. AGSL has only one location and is typically tighter, but tends to swing to one side or the other in specific categories for a while, followed by an internal correction toward center.

 

[Coconutpalm]

I want to post these videos just to show everyone the clarity of the diamonds first. These videos were taken in different offices, but with similar fluorescent lighting. I will try to get a video with both diamonds side by side in the same lighting conditions at a later time.

If you have a preference based off the videos below I would love to know. In order to get an unbiased opinion I will label them A and B. Will reveal which is which at a later time.


Diamond A: Office lighting/Florescence
https://streamable.com/1d5jg

Diamond B: Office lighting/ Florescence with large window (mid afternoon sunlight)
https://streamable.com/2hgkm

 

[John P]

Interesting insight, thanks for clarifying @John Pollard!

On the one hand... I’m thinking “how lovely to find such an upstanding vendor!!”
On the other, though, I’d be lying if I didn’t say part of me winced.

I will say that my field is one wherein anything and everything can and will be used against you, so not taking advantage of a lucky break would be... inadvisable. I can’t claim to know your pipeline at all, so I guess I’ll just say that I hope that the supply chain with which you deal so honestly is (and remains!) as just in its dealings with you

Indeed, we choose our network of dealers for sharing that quality. Thank you @yssie. Tip of the hat.

I'd also add that we're not a 'vendor' (aka retailer). We are a producer. That means we assume the majority of our risk upstream from grading. We purchase starting crystals in the blind, based on results we calculate based on our expertise. If we do our job correctly they run on the wheel and finalize just as we calculated. All good. No need to accept 'lucky grades' that could potentially damage the brand's rep.

 

[whitewave]

Obviously, as a CBI owner I say CBI. I have SI2 (.56 though) and there is nothing wrong with it performance wise-- you can trust CBI for their decision to sell SI2. And if you happen to not like it, just switch it out. Easy peasy.

 

[diamondseeker2006]

Thanks, John. You originally said that CBI sometimes asks the lab to recheck for a lower grade, and the only reason to ask for a downgrade in color is if you think it was graded too high. All CBI stones are graded by AGS, right? I do agree that they sometimes grade higher in color. So it's good to know if you think they overgrade, you try to correct it. That's a good thing for buyers and was all I meant!