Interested in a ring. Input?


May 25, 2016
I am not a ring expert, however I am currently searching for my own ring. I think the stones at Costco seem really nice (and they have GIA reports, etc), and I like that pretty much all of the e-rings are platinum.

For this ring, I think it is a great price considering the size of the stones.

That said, I would be worried about the shared prongs on this ring. I'd wonder if that kind of design is risky to losing stones.

Costco has a fantastic return policy, so that aspect would comfort me.

I am curious to see what the seasoned regulars think.

Dancing Fire

Apr 3, 2004
Hard to guess the "cut quality" w/o the GIA report.


Aug 8, 2005
Round Diamonds 101:

The entire purpose of faceting a diamond is to reflect light.
How well or how poorly a diamond does this determines how beautiful it is.
How well a diamond performs is determined by the angles and cutting. This is why we say cut is king.
No other factor: not color, not clarity has as much of an impact on the appearance of a diamond as its cut. An ideal H will out white a poorly cut F. With round diamonds even a GIA triple Excellent is not enough. And you must stick to GIA and AGS only (HPD in Europe is good as well). EGL is a bad option: [URL=''][/URL]
So how to we ensure that we have the right angles and cutting to get the light performance we want?
Well one method is to start with a GIA Ex, and then apply the HCA to it. YOU DO NOT USE HCA for AGS0 stones generally, though you can. In general, AGS0 trumps HCA though as one examines the actual stone and the other does not.
The HCA is a rejection tool. Not a selection tool. It uses 4 data points to make a rudimentary call on how the diamond may perform.
If the diamond passes then you know that you are in the right zone in terms of angles for light performance. Under 2 is a pass. Under 2.5-2.1 is a maybe. 2.6 and over is a no. No score 2 and under is better than any other.
Is that enough? Not really.

So what you need is a way to check actual light performance of your actual stone.
That's what an idealscope image does.
It shows you how and wear your diamond is reflecting light, how well it is going at it, and where you are losing light return. That is why you won't see us recommending Blue Nile, as they do not provide idealscope images for their diamonds. BGD,BE, James Allen, GOG, HPD, ERD and WF do.

The Idealscope is the 'selection tool'. Not the HCA.
So yes, with a GIA stone you need the idealscope images. Or you can buy an idealscope yourself and take it in to the jeweler you are working with to check the stones yourself. Or if you have a good return policy (full refund minimum 7 days) then you can buy the idealscope, buy the stone, and do it at home.

Now if you want to skip all that... stick to AGS0 stones and then all you have to do is pick color and clarity and you know you have a great performing diamond. Because AGS has already done the checking for you. That's why they trade at a premium. Some AGS0's are better than others though, so pay attention to any ASET or IS provided.

In general with rounds, you will want a table 60% or less. A depth between 59 and 62.4. Crown angle 33.5-35. Pavilion Angle: 40.6-40.9 (there is a little give on this). And the crown and pavilion angles must be complimentary which is what the HCA checks for you.

On color:

It is important to remember is that color is graded FACE DOWN. Where there is NO light return. Not face up where there is light return and refraction. You wear diamonds set. FACE UP.


Within one color grade, even the labs can't agree on the color grades of stones and something could be a "high" H or a "low" E. Within 2 color grades it is hard. Not impossible. But very hard. And it gets harder once set. If you are talking ideal rounds, or any stone with ideal light return and no sharp corners it gets harder still because the ideal light return masks body color.

Generally we say to be conservative stay above H if you DO NOT KNOW YOUR LADY'S COLOR PREFERENCES.

If you are talking fancy shapes without ideal light return (because there is no 'ideal' for EC's Radiant, etc) it's a bit different.

This is how I think of it.

Ever gotten one of those HUGE paint fan decks? Where there are literally 100s of colors of whites? And when they are RIGHT next to each other you can TOTALLY tell that one is bluer/colder and one is a bit warmer and which one is one is TOTALLY warmer. One there's one that's slightly greener. One that's slightly pinker? But really. They are all white?

Then you pick one after agonizing over this white or that white and when it's on the walls and people are like: Oh. You painted again. And it's STILL white. Great.

And you're all... BUT it's BLUE white. Or it's a WARM white now. It used to be ____ white. It's TOTALLY different.

It's like that. You are talking about shades of white. D is colder... J is warmer. But it's all white.

YES. If you have an accurately graded F and an H THAT HAVE THE SAME PERFORMANCE you are going to be able to tell them apart when you compare them side by side. Just like you would be able to tell if you painted your walls a warm white, but painted the crown molding a cold/straight white. But both are STILL white, you only see the contrast because of the proximity. But it's very slight, you could set an F center with G sides and never tell the difference. And even H sides depending on the setting and the size of the sidestones... especially with round brilliants.

I want you notice all the qualifiers thought. I'm talking about stones with the SAME performance. An ideal H will out white an F that has compromised light performance from a poor cut.

NOTHING impacts the appearance of a diamond as much as cut. CUT is king.

You want the shinest whitest and brightest diamond out there: Cut is King. No other factor, not color or clarity or anything else impacts how white bright an shiny a stone is.

On Clarity:
Clarity Vs2 or Si1 and eyeclean is as high as you need to go in a round. So set that as a floor. And verify eyeclean with vendor or images and vendor (best). An Eyeclean SI1 will look just like an IF to the naked eye. So... really anything over VS2 and eyeclean is just because you want higher clarity for some personal or cultural reason (and that's fine of course, just make sure it's an educated decision) or because you are getting a good deal on a stone because higher clarity stones can be harder to move (especially in lower colors). So make sure you don't put a CEILING on your clarity. All you need is a floor. And with rounds, in general that floor is Si1 or Vs2.


Jun 23, 2005

For comparison, here is a super ideal cut I color, VS2 clarity diamond. We have no way of knowing the cut specs on the center diamond of the ring you are considering but we can see that the diamond above has stellar cut quality.

You can certainly find or have made a mounting similar to the one pictured. I would probably suggest going with a three stone for the simple comfort of the ring. You could also find a multiple stone ring with the rest of the shank in pave diamonds. Having that many stones across the top of the finger could be uncomfortable between the fingers.

Have you actually seen the ring in person?


Dec 17, 2008


Jul 27, 2011
Will Costco let you select the center stone? Or is it pot luck and you get what you get?
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