How much does cut really matter?

[aliza3]

How much does cut really matter?
I heard that cut is what makes the diamond sparkle and that it is the most important C.
Is this true? Will a diamond that is rated "good" for cut, by GIA, look amazing? I am deciding whether to get the color and size stone I want or to go down in those two Cs and go to up to an excellent cut. Please let me know what you would recommend.

Thanks!

 

[kenny]

Imagine installing a mirror on a wall near a corner and angling it towards the corner so you could never see yourself in it.
That's how stupid a poorly cut diamond is.

A well cut diamond puts the facets in the right place so maximum light is returned to your eyes instead of leaking out the back and sides.

Most diamonds are poorly cut because that saves more of the weight of the original rough diamond.
Good cut polishes away more rough.

Few buyers understand the importance good cut but they all know about weight, as in, "I'm looking for a 1 carat diamond".
Why should sellers cut diamonds well?
Few do.

Now that you know better … get a well cut diamond.
If you want a round diamond find ones with HCA scores under 2.0.
Plug four numbers from the GIA or AGS report into the HCA.

https://www.pricescope.com/tools/hca

Get Idealscope pic on those that score under 2.0.

https://www.pricescope.com/tools/ideal-scope

Compare them to this chart.



Only consider diamonds graded by GIA or AGS since you cannot believe the color and clarity grades issued by many other labs.

 

[Gypsy]

Yes it is true.
The single most important characteristic that affects how white, bright and fiery a diamond looks in all lighting conditions and when dirty (cause it's pretty much always dirty when you are wearing it, except immediately after cleaning) is cut. Cut impacts everything.


Compare for yourself: All H VS2 at 1.20-1.30 carat weight.
http://www.jamesallen.com/loose-diamonds/round-cut/1.22-carat-h-color-vs2-clarity-sku-284269 Ideal (AGS 0 light performance)
http://www.jamesallen.com/loose-diamonds/round-cut/1.29-carat-h-color-vs2-clarity-very-good-cut-sku-58227 GIA Very Good
http://www.jamesallen.com/loose-diamonds/round-cut/1.28-carat-h-color-vs2-clarity-good-cut-sku-58729 GIA Good cut

Also GIA Ex is too broad. You want to narrow that down. Stick to AGS0 stones or GIA Ex stones with a good HCA score https://www.pricescope.com/tools/hca (under 2.5 is fine) from a vendor that provides idealscope images so you can verify light performance.

And here is a thread you might find interesting:
[URL='https://www.pricescope.com/community/threads/likelihood-of-finding-a-signature-super-ideal-diamond.174235/']https://www.pricescope.com/community/threads/likelihood-of-finding-a-signature-super-ideal-diamond.174235/[/URL]

And a link: http://www.goodoldgold.com/Diamond_Videos

 

[distracts]

Will a diamond that is rated "good" for cut, by GIA, look amazing?

No. "Good" is squarely middle-of-the-pack when it comes to GIA cut grading. "Excellent" is the top, but "Excellent" is a very broad category. I've seen a few determined PSers dig through "Very Good"s to find the strange outlying "Very Good" that had an awesome cut, but I've not ever seen that happen for "Good." And in person, the difference between an amazing cut and a not-so-amazing one IS noticeable.

 

[aliza3]

So If I have a diamond that is 1.5 carats and D color but good cut and another that is 1.33 carats and F color but excellent cut, you would got for the excellent cut one?

Thats basically the tradeoff I keep encountering- to go smaller and worse in color but better in cut.

 

[Gypsy]

So If I have a diamond that is 1.5 carats and D color but good cut and another that is 1.33 carats and F color but excellent cut, you would got for the excellent cut one?

Thats basically the tradeoff I keep encountering- to go smaller and worse in color but better in cut.

Again. Read what I posted for you, for the love of Pete. And do some research. Before you spend 10K on something you know nothing about!

https://www.pricescope.com/wiki/diamonds/diamond-cut Read this, and then all the links it sends you to.

 

[TC1987]

To answer the 1.33ct vs. 1.5ct question:

Round diamond face-up size is the area of a circle, pi D squared divided by 4. From high school math, haha.
Check my assumptions here, but I am going to presume that most ideal cut 1.33ct are about 7.2mm in diameter, and most ideal 1.5ct RB are about 7.4mm diameter. So, side by side, you'd probably notice that one is a tiny bit larger than the other. But probably not a significantly larger diameter. And then you have to figure that a superideal or ideal cut diamond has not dead spots in it, and that it also reflects back all of the light rays. And probably the "good" cut diamond is not as lively, may have dead spots, windows, or a good deal of leakage. It's slightly larger size isn't compensating for the deficiencies in the cut. Good Old Gold has some videos posted where they compare a GIA good to a GIA or maybe AGS triple excellent. And you can see that the "good" is a dimmer and quirkier stone than the superideal. That is usually the way it works in real life, if you compare the average grade of diamond to the best of the best that PS people recommend.

 

[Gypsy]

Pickings are slim in the range you are looking at right now -- ideal light return F-H VS2-Si1 1.30-1.5 ct. and under $10,8000. BGD, GOG and WF had nothing in house for you. But I did find 3 worth your time at James Allen. They have a no questions asked 60 day return policy and they will pay shipping both ways.
They have gemologists on site that can evaluate if a stone is eyeclean or not for you.

http://www.jamesallen.com/loose-diamonds/round-cut/1.40-carat-h-color-si1-clarity-excellent-cut-sku-270387 If eyeclean this is my first choice for you as it eeks out the most size at 7.2 mm. Get an idealscope image as this one is does not have one posted.

http://www.jamesallen.com/loose-diamonds/round-cut/1.35-carat-h-color-si1-clarity-excellent-cut-sku-282329 Second choice as it is the most budget friendly of them all. If eyeclean. Idealscope images is posted and looks great. (You don't need the HCA once you have the idealscope image)

http://www.jamesallen.com/loose-diamonds/round-cut/1.35-carat-h-color-vs2-clarity-ideal-cut-sku-272364 This is the 'safest' choice. It is an AGS0 (so you do not use the HCA) and it has a great idealscope posted, plus it is going to be eyeclean. It's also the priciest which is why I saved it for last.

 

[c-k]

Diamond cut does matter, you could have a D - FL- Poor cut dog or a H - VS2 - Ideal cut stunner

Get the best cut stone you can find, get a Ideal cut, then work around the Clarity/Color/Carat.

 

[GeorgeStevens]

If the pickings are slim, wait a bit. Gem-quality diamonds are mined and polished year-round, but retail sales disproportionately happen in a couple of months, principally between Christmas and St. Valentine's Day. So occasionally inventories will get low, but if you're patient the supply will quickly recover. Being patient would be a virtue that will be repaid in getting a better diamond. This will also allow you to explore more options and become more educated on what you're spending your hard-earned $$ on.

 

[JulieN]

The supply is low bbecause he wants an exceptionally high color for an exceptionally low price

 

[MarionC]

Read what I posted for you, for the love of Pete. And do some research

Thanks for the first grin of the morning.

 

[GeorgeStevens]

The supply is low because he wants an exceptionally high color for an exceptionally low price

Don't we all?

But seriously, the worst way to buy a diamond is on this forum all the time: someone who knows next-to-nothing, doesn't want to take the time to educate themselves, but wants a deal, and wants to propose this weekend so can't wait. Patience helps someone learn, which is the only hope they have against overpaying for a lousy stone.

 

[Dancing Fire]

The supply is low bbecause he wants an exceptionally high color for an exceptionally low price

They don't grow on trees...