Diamond Shape vs Cut, Square Diamonds

Simple diagram of diamond from GIA|GIA Diamond Anatomy||gia old mine cut diamond diagram|spready diamond|Profile pic of a diamond in tweezers.|

Parts of a Diamond. Courtesy of GIA

Shape vs Cut of Diamonds, It’s Not Enough to Know the Shape You Want. Shape and cut are often confused but know this: they aren’t the same thing.

If you confuse the two, you may ended up making an unfortunate purchase like Nate did. (See below story)

I’m going to explain what the difference is in this article between diamond shape and diamond cut. Let’s start with shape.

Diamond Shape

Shape refers to the basic external outline of a gemstone. Round, oval, square, triangular, heart, marquise, and pear are all shapes. And they all describe shapes of diamonds you might be looking for.

Guy Friendly Analogy

Soccer balls and basketballs are the same shape and can even be the same color. But are they the same? Not by a long shot. Any kid can tell the difference between the two.

It may take a trained professional to recognize the differences between two round diamonds, but you’ll always be able to identify its shape. Round is round!

Diamond Cut

Identically shaped stones can be cut, (faceted), differently. A round stone can be cut with any number of facets and dimensions—and still be round!

In the jewelry world “cut” with diamonds does not refer to shape (round, oval, etc.), but the symmetry and proportioning of a faceted stone. A diamond’s cut greatly effects its brilliance. The more skillfully it’s been cut, the more sparkle and pizzazz it will show.

Another Guy Friendly Analogy

Two round tires of the same size can have completely different tread patterns. Their shapes are the same. Their cuts are not. Similarly, two cars of the same year and model will have the same shape yet may be trimmed differently. One may be a convertible, the other a hard top. One has tinted windows, the other doesn’t. One is painted a metallic red, the other basic white.

Soccer balls and a basketballs are both round. But are they the same? No! You get the idea. Just because two diamonds are both round, doesn’t mean their cuts are the same. One might be what’s called a “round brilliant.” The other might be an “old European cut.” The former has more facets than the later and will typically be more bright and shiny. But they’re both round shaped!

Where Diamond Naming Can Get Confusing

The Facet Pattern of a Radiant Cut Diamond is Noticeably different Than the Emerald cut.

One of the confusions you’ll run into is that some diamond shape names have had the suffix “cut” appended to them. For example an “emerald cut” diamond refers to the stone’s square or rectangular shape and the way it’s normally cut.

An emerald cut is unique in that the corners are notched making it easier to set and making its corners stronger.

In the jewelry industry if someone says to me, “I have an ‘emerald cut square’ diamond to show you.” I know that it is square in shape and has the unique notched corners of an emerald cut. And it has the unique step cut that sets an emerald cut apart from one of the other cuts I write more about below.

Sometimes both the shape and the cut are used in the diamond shape name to identify a single stone. A “round brilliant” diamond has a round shape and a brilliant cut.

What Does the Love of Your Life Really Like in Square Diamonds?

The reason it is so important to know the difference between shape and cut is that it is easy to think you’ve heard what she loves in diamond shape and cut when you have not.

Your fiance may not realize that there is a special name to the shape and cut she loves.

The Princess Cut Diamond That Fell Flat

My client Nate found me on the internet. First he had bought online a “square” diamond for his fiance. He chose a princess cut diamond. “It’s square right babe?” Weeeellllllll….. she actually didn’t like the hard angularness of the princess cut diamond.

What she’d really wanted was a cushion cut diamond, but she’d called it square. He called me to help with damage control. I met with him and his fiance. I went over all the different choices of “square” shaped diamonds. Kiki let me know that what she really had in mind was “that one.”

And she pointed to a cushion cut diamond.

Nate said, “well it’s not exactly square!”

I let him know that it fits in the “square” spectrum when choosing diamonds.

Long story short Kiki is now wearing a ring I designed with a cushion cut diamond on her hand and she does look better with the softer outline of a cushion cut diamond.

The moral of the story is that it is especially critical when your fiancé is interested in a “square diamond” to get a bit more specific on which cut she likes.

Princess Cut vs Cushion Cut, There’s a Big Difference!

Does she want a princess cut with its angular, sharp edged corners? See the picture at the top of the article.

Does she want a cushion cut which is like a princess cut, but with rounded corners and rounded edges for a more feminine look?

Both the princess cut and cushion cut have around 58 facets for lots of brilliance in look. But they differ in shape slightly. That difference between hard angles and softer curves is subtle, but very important.

Emerald Cut Diamond vs Radiant Diamonds

Does she want a square emerald cut diamond? Its faceting pattern shows the beauty and depth of the diamond. The emerald cut is not as sparkly a cut style as the princess cut or cushion cut.

A radiant cut diamond shares the notched corner look, which makes it look similar in outline to the shape of an emerald cut diamond. But a radiant cut uses different and more sparkling facet patterns. The radiant diamond is more modern than the emerald cut diamond. (See picture a few pics above.)

If she likes the notched corners like she’s seen on emerald cut diamonds you’ll want to know if she wants more sparkle or more elegant subtlety. Also see Asscher diamonds below.

The emerald cut uses a step cut facet pattern which is especially good for pairing with a vintage style ring design or a simple and classic style.

Asscher Cut Diamond

Does she want an Asscher cut for a more classic vintage look? The Asscher is a bit more out of the ordinary. If your fiance is looking for the square shape, but seeks a more seldom trod path then the Asscher is a wonderful choice.

It is cut more deeply than an emerald cut pattern and sparkles more. The Asscher uses a step cut style for a more old school vintage look. Its cut combines sparkle and a mirrors of infinity look, when you gaze down deeply into it.

Just a little detail. The Asscher diamond is cut more deeply than an emerald cut. This means that more diamond weight is captured in the underside of the diamond. For this reason you need to get an Asscher diamond that weighs more for the same size look as an emerald cut. This makes Asscher diamonds more expensive.

Now You Officially Know Your Shape vs Cut in Square Diamonds

“What?!? She just changed her mind to an oval shape? Well dude that’s the subject for another blog post.”

May Your Diamond Selection Bring You a Lifetime of Happiness.

Your Diamond Jeweler,
Calla Gold

Check out my other diamond selection blogs starting with “Shopping for Diamond Clarity, How Perfect Does it Have to be?”





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About Calla Gold

Calla Gold is a Personal Jeweler and Author who takes pride in working with clients one-on-one to integrate their personal sense of style and taste into custom designed jewelry and repaired jewelry pieces.   Unlike typical Santa Barbara jewelry businesses, Calla Gold has no brick-and-mortar location. Calla Gold comes to you, bringing you the jewelry collection you want to see and collaborating with you to create unique custom jewelry. Calla also works with at-a-distance clients.

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Amy Marie Orozco
9 years ago

Diamond shapes and cuts … who knew there were so many differences? Calla Gold, that’s who. And, I never realized that I really like that cushion cut diamond. Never really thought about it. I’m getting such an education.

Leecy Madison
9 years ago

I really like the princess cut and the cushion cut. I don’t sell diamonds yet and I can’t afford to buy many. I also like channel sets and cross overs. I’m an odd ball and I always want something different.
You blog is great and very informative. It’s obvious that you put a lot of time into your blogs–there are so many of them.

Merry Christmas

Tracey M.
Tracey M.
9 years ago

This is really a helpful dive down into pretty diamond details here. There really are a lot of distinctive diamond shapes that can be called square if you don’t know the difference.
Thanks for the helpful pictures too.

Linda Menesez
9 years ago

What an fantastic amount of information in this article, Calla! I had no idea that the cut would make such an amazing difference. Your blog is truly educational.


Patricia Schwartz
9 years ago

Calla, this article on square cut type diamonds should be used to inform the next generation of jewelers! I especially liked Nate and Kiki’s “square diamond” story. This article of yours promotes good communication. I approve. Very informative!

Marge Buelow
Marge Buelow
8 years ago

Do you know if a plain old 1/8″ wide ring band can be reworked into a “football” shape? and can a CZ in the same shape be mounted in the center with that newish style where it seems to be shimmering? I assume it would need to have a bale/chain added. The ring is about a size 7 or 8. Do you have a recommendation on carat size to look attractive?