What’s the Most Expensive Diamond Cut?

What’s the Most Expensive Diamond Cut?

When you judge the 4Cs of diamond quality – Color, Clarity, Cut, and Carat Weight – you weigh most of the factors that influence how much it costs per carat.

But there’s one big factor that can affect the price of a diamond by as much as 30 percent that gets MUCH less attention. In fact, you may not have considered it in your calculations at all.

That factor is the shape. Diamond shape influences how large a diamond looks on your finger in the engagement ring itself. It also influences how much it costs per carat.

What is the most expensive diamond shape? The round brilliant! It’s also the most popular shape.  (Yes, those two things are related.)

The round brilliant used to be the easiest diamond shape to buy because gem labs issue grades on proportions. Anyone can tell how well a round brilliant is cut just by looking at the cut grade.

Fancy shapes are a bit more complicated, with more factors to consider and no easy “ideal” proportions. Length and width ratios and a wider variety of proportions means that there is a wider variety of cut quality for fancy shaped diamonds.  Let’s be frank, here: there are a lot more fancy shapes that aren’t well cut out there on the market.

But now that you can let ROSI find you a diamond and use artificial intelligence to weigh all the complicated factors that tell you how well a fancy shape is cut, buying fancy shapes is a lot easier than it used to be. ROSI protects you from buying the diamond version of a lemon by weighing even more cut parameters for fancy shapes, making sure that you buy a diamond with lively sparkle and brilliance that you will love forever. (Shhhh. Not everyone knows this yet and the prices for these more unusual shapes still haven’t caught up.)

Picking a fancy shape instead of a round can save you up to 30% over a round brilliant of the same color, clarity and carat weight. So here are our favorite fancy shapes and how much you might save by choosing them instead of a round brilliant. Since there are hundreds of different grades and sizes and the market’s always changing, your mileage will vary, of course.

Here are our six favorite shapes for offering value for money on your engagement ring.


Cushion Cut

Why do we love cushion cut diamonds?  You get everything you love about a round brilliant plus a cool vintage vibe. Cushion cuts are almost as brilliant as rounds. We recommend choosing a square shaped cushion cut rather than a rectangular one because of brilliance. Square cushion cuts are the only fancy shape that can show hearts and arrows, the precise pattern that demonstrates a diamond’s exceptional light performance. Our Cushion Brilliant is a cushion cut that is as brilliant as a round, with the hearts and arrows to prove it!  Cushion cuts are also one of the most affordable fancy shapes. And premium hearts and arrows cushions like the Cushion Brilliant also cost less per carat than regular round brilliants but will be more brilliant.


Oval Cut

Why do we love oval diamond cuts? They are brilliant and elegant, with an elongated shape that makes your fingers look longer. (Have you seen Blake Lively’s engagement ring? Swoon.)  Something else to love about ovals?  They look larger than other diamond shapes of the same weight.  AND they cost less per carat too.  You can save $1000 on a one-carat diamond in some qualities. So you have a diamond that looks larger and costs less per carat than a round.  You’re welcome.


Pear Shape

Pear shapes are having a moment, with Ariana Grande and Cardi B being just two of the celebrities with pear shape engagement rings. Pear shapes are the most unique cut because they are really a combination of a round and a marquise.  That does mean there are some pear-shapes out there that aren’t very well-cut.  But when you find a good one (or let ROSI do it) you have a unique diamond with the elegance of an elongated shape. And your pear-shaped diamond looks larger than a round and also costs less per carat. Similar to an oval, you can save $1000 on a one-carat diamond in some qualities.


Radiant Cut

Radiant are square or rectangular brilliant-cut diamonds with cut corners. They are often the most affordable diamond shapes. They are similar to a princess cut but with eight sides rather than four. The clue as to why the radiant isn’t more popular given its geometric style and affordable price comes in its history: originally developed as a cut for fancy shapes, the radiant cut can concentrate color and make a diamonds cut more noticeable. That’s great for fancy colored diamonds, of course, but not as good for colorless gems.  If you plan to set your diamond in platinum or white gold, you may want to buy a better color. The good news is that you’ll be able to afford it: you can save 30% or even 40% in some sizes and qualities on radiant cut diamonds.


Emerald and Asscher Cuts

If you love cool icy emerald diamond cuts, with their long flashing facets you don’t care how much they cost. Emerald and asscher cuts are both step cuts, a style of faceting with larger facets that create rectangular reflections rather than small triangular reflections of brilliant cuts. Both are much less than round brilliants, if generally a bit more than a radiant. They do show inclusions more than brilliant cuts so you may decide to trade up in clarity from what you would choose for a round brilliant. Expect to save 25% or even more over a round brilliant.


Princess Cut

Princess cut diamonds are designed by diamond cutters to save weight and look good doing it: they are the closest to the shape of a diamond crystal so they often yield larger stones from the rough. The four-cornered style of the princess looks good in many ring designs too. Choosing a princess cut might save you 20% over a round diamond.

Honorable mention: Marquise cut diamonds are not necessarily the most expensive, but they are quite beautiful and radiant and certainly at least deserve an honorable mention.

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