I check Costco prices and quality of diamond rings against the price and quality of other highly reputable online jewelers.
I compare by the data and the specs.
Today’s Costco diamond is this Square Emerald Cut 1.70 ct VVS2 Clarity F Color Diamond Platinum Solitaire Ring. (It’s one of a kind, so it could easily have gone out of stock since I mentioned it here. However, you can bet that Costco will have another one just like it in specifications. So this comparison should be useful.
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Bottom line: you’ll save $2,660 on a ring with the same specs at James Allen.
You’ll save $2,660 by buying a diamond ring with the same specs at James Allen.
To see how easy it is to build the ring at James Allen, scroll to that easy section below.
Costco’s offer: $14,699.99
This is Costco’s item number 939083.

The specs
GIA diamond certificate
It has a GIA diamond certificate. This is a necessity for any expensive diamond. Never buy one without a grading report from the GIA, AGS, or IGI. Of course James Allen will have such a grading report too. But it’s nice to see that the big box store, Costco, is meeting this must-have, minimum requirement.
Shape
It’s a “square emerald,” or also known as “Asscher” cut. This cut emphasizes depth and transparence. So the clarity of the diamond is especially important in this cut. As is the color.
(Also important: where are any of the inclusions (flaws) located within the diamond?) You’ll need to check out the GIA report on it here.
Carats
This diamond weighs 1.7 carats.
Clarity is VVS2
That’s a high clarity score. Important for this cut, as already mentioned.

Color is F
That’s a high grade in color. That’s important with this cut, especially. (Remember, there are no A, B, or C color grades. The best possible color, perfect, is graded as a D.)

The setting (the ring itself) is Platinum
Platinum is … awesome.
Now for James Allen’s offer on a ring with identical data and specs: $12,040
That’s $2,660 less than Costco’s offer.

The James Allen offer has all the same specs.
In fact, the specs are slightly better. The James Allen diamond I happened to find weighs 1.77 carats, which is slightly larger than the 1.7 carats of the Costco diamond.
The James Allen offer also has a GIA diamond certificate.
Even better, you can see exactly what your exact diamond looks like, using James Allen’s 3D imaging of virtually every diamond in their inventory.
How to build a ring like this at James Allen, and save $2,660 or more:
- Select this setting at James Allen. Add it as the setting you want to then place a diamond on.
- Go to the James Allen diamond inventory search tool (so easy to use) and set your filters/sliders as shown in the image below. (The link may already do that for you. But if not, then just do it manually.

Then it’s easy! You just add a diamond that you like.
And when you get ready to check out, you’ll see that you have a ring that saves a ton of money.
It has the same specs and data as the Costco ring. But you’re saving a lot of cash.
The one reason, as always, that the Costco ring might be worth the price premium
If you’re in a huge hurry to get the ring, then Costco can get it to you faster. That’s because James Allen custom creates your ring. Costco’s rings are sitting in a warehouse. Ready to ship.
Enjoy your shopping! You can totally get a ring you love at a price you can afford.
It’s easy to get great deals on better diamond jewelry — for less money! Here’s how:
- Scroll up to the section on “How to Get the James Allen Deals.”
- Follow the easy directions there.
- Feel 100% confident that you bought the best diamond for the money
How to search this site to save up to tens of thousands of dollars at trusted diamond retailers, vs most any Costco, Kay, Jared, or Zales ring you’re considering
Search and save. You could save enough for a new compact car. Or a honeymoon. Or several expensive dinner dates. Or that guitar you’ve been wanting.
Read this very short note on how easy it is.