Round VS Princess Cut Diamonds – 7 Differences To Help You Choose

If you’re looking for diamonds for an engagement ring you’re likely looking at two of the most popular shapes and style cuts, namely the round brilliant and the princess cut (also known as square). Both are highly popular diamond shapes, and they both offer a lot of sparkle but they look quite different and they work a bit differently in a ring (or any jewelry).

Today we’re comparing these two beauties so you can have a better idea of the pros and cons of each. No amount of reading will ever equate to actually seeing the diamonds in person though, so be sure to go to a jeweler and compare a round with a princess to see for yourself their light performance and how they sit on your finger. Until then, let’s talk details.

Round vs princess cut diamonds

Round cuts are more popular than princess cuts, and are about 30% more expensive. Traditional round cuts are optimized for maximum sparkle, while the princess cut sparkles a bit less. The round cut offers that classic elegant look ang goes with anything, while the princess cut is a more modern aesthetic and fits better with a clean, crisp, minimalist style. The corners of a princess cut are sharp and need to be protected with prongs or a bezel setting, while a round cut is safer and can be set in any way.

Both the round and the princess cut have variations and they can be a bit difficult to navigate, especially when the differences are slight. So both cuts require a great deal of patience on your side. They also hide inclusions very well, since they are both brilliant cuts so that may help you get a better deal for your diamond.

What is a round cut ?

A round cut diamond is a type of brilliant cut (as opposed to step cut) which is derived from the old European cut. In fact the round brilliant cut has been calculated for a diamond’s refractive index of 2.42 which means it has the maximum amount of fire and brilliance possible in a diamond.

round old european

The round cut is the go-to diamond cut shape, and most of the diamonds on the market are cut like this. One, they offer the best performance so both the sellers and the buyers are happy. And two, it has become such a classic that few people stray from this shape. The default engagement ring is a 1 carat round-cut diamond solitaire, prong-set in a white gold band. You surely know a few people who have that exact ring.

Some take comfort in knowing their ring is traditional, some want to change things up. But you cannot deny this is the most common and sought-after diamond cut. There are many, many variations and minute improvements on the round brilliant so you will need your jeweler to be patient and show you several versions.

What is a princess cut ?

The princess cut is another brilliant cut style, and it looks like a square when viewed from above. This cut has sharp 90 degree corners, which need protection so they don’t hurt you, snag on something, or break the diamond (it can happen).

A princess cut has its facets arranged very differently from a round brilliant. The pavilion is where it differs the most, as it has chevron-type facets instead of triangle or arrow facets. The result is a very splintery, geometric look that still looks like a brilliant cut and not a step cut.

princess cuts
Two of the most common princess cut styles

The princess cut hasn’t been around as long as the round brilliant but it has gained significant popularity over the last few decades, to the point where it is the second in sales after the round cut. Now let’s compare the two.

1. Round cuts are a classic look, princess cuts are more contemporary

The round cut diamond is a classic look, it is timeless, it is elegant, and it is something your mother and possibly grandmother also wore. This can be very charming and comforting for many women, as it brings extra sentimental value. Some consider the round-cut diamond to be THE engagement ring diamond.

This diamond cut is also far simpler or easier to wear and pair with absolutely anything, because the shape is quite neutral and goes with anything. The style doesn’t stand out too much, it’s not outlandish, and it goes just fine with a modern outfit.

Meanwhile the princess cut is more of a contemporary diamond cut, preferred more by those who like to have a modern style (fashion, furniture, lifestyle) but this doesn’t mean they are the only ones wearing the princess cut. There is no denying the princess cut is something you’d much rather find in engagement rings from 2010 onwards.

Princess-cut 3 ct diamond solitaire with knife-edge 2-row pave band in platinum. See it on Amazon.

2. Princess cuts offer an angular look, round cuts are softer

The look of the diamond matters a lot when deciding which to get. If you’re not the one wearing the diamond then it’s worth looking as your loved one’s jewelry and general style to see what she usually goes for. A princess cut offers a more angular, polished, clean look that goes very well with modern aesthetics.

The square shape is also something that not many people can pull off, precisely because of that angular look. For example very skinny and long fingers may pair better with a princess solitaire than short, stubby fingers. But short stubby fingers may look better with a round cut or even a cushion cut (neither a square nor a round).

The round shape of the round cut is softer, more organic-looking and as such it doesn’t stick out as a princess cut would. This makes it much easier to wear and blend into your personal style. If you’re someone who doesn’t want to stand out too much, not comfortable with extra attention then the round cut may be a better choice than the princess cut.

3. Round cuts are more expensive than princess cuts

There is a significant price difference between round cuts and princess cuts, in fact it’s about 30% ! Round cuts are the highest priced diamonds out there, while princess cuts fall far below the usual price of a round cut. Here’s a few examples form reputable online sellers, and you can check these prices for yourself.

On Bluenile we searched for a round brilliant, 1.00 ct, E color, very good cut, VVS1 clarity. The highest price was $15,353 and the lowest was $9,661. On the same site we searched for a princess cut with the same specs/filters as the brilliant and found the priciest at $9,911 and the lowest price at $6,620.

On Jamesallen a round brilliant with the same specification as the Bluenile one (1.00 ct, E color, very good cut, VVS1 clarity) is between $12,727 and $8,337. And we looked for a princess cut on Jamesallen as well, again with the same specs as before, with a prince range from  $8,159 to $5,303.

One thing you’ll notice here is that the lowest price for a round cut is pretty much the highest price for a princess cut. Why are round cuts priced so high ? Three reasons:

  • they simply can, as round cuts are the most popular and bring in the most revenue no matter their cost
  • a lot of rough is lost when cutting a round brilliant, so a bit of profit must be added
  • there are so many variations and improvements on quality that a slightly different cut can up the price by several thousand $

So there you have it, the round brilliant is the most common, most popular, but also the most expensive (about 30% more). So the same money can get you a not-the-best round cut or the absolute best princess cut, if you’re looking to switch from round to square.

Lab-grown 5ct diamond solitaire (D-E color, VS1-2) set in platinum on a plain band. See in on Amazon.

4. Princess cuts have more brilliance, round cuts more fire

Let us explain what we mean by brilliance here. Brilliance is the white light reflected by a diamond, while fire is the colorful light. In all the comparisons we’ve seen, princess cuts seem to have more white light than a round cut. This is most apparent in office lighting or on a cloudy day (diffused light).

Meanwhile the round cuts have been calculated to maximize the fire in a diamond. They do have some white light as well, but they have the most fire out of all the diamond cuts. Princess cuts have their own fire too, but compared to a round brilliant they fade a little.

5. Round cuts appear smaller than princess diamonds

The weight of both round and princess cuts is in the pavilion, but they are shaped differently. Because the princess cut is a square, it appears slightly larger on the finger than a round cut. This can mean a lot if you’re dealing with smaller carats of have a diamond under 1 carat as even 1 millimeter extra can make the diamond appear that much bigger.

All diamonds look larger once they’re set, if you choose the setting correctly. For example a round cut with a bezel setting that also has filigree detailing will look larger than one with a prong setting. The bezel doesn’t have to reach all the way down to the shank, it can just be a band keeping the girdle safe, supported by prongs, so something like a basket or gallery setting.

Another way to make your round cut appear larger, and possibly even mimic a princess or cushion cut, is to use a triple prong setting. So that is 4 corners but instead of a single prong on each corner, use three. The middle prong larger, the side ones smaller. Do this with white gold or platinum and the diamond will look almost like a princess in shape.

6. Princess cuts need corner protection, round cuts are safer

Princess cuts have very sharp corners, and as beautiful as they are, they are a weak point in any gemstone, including diamonds. While a diamond does not scratch, it may cleave if it’s hit in the right place with the right amount of force. Those places are usually the very sharp points of a princess cut, a baguette, or a lozenge.

Read also: Oval VS Pear Diamond Cut

So princess cuts always get a prong on their corners, or a full bezel setting that covers all corners. This can work very well for some people, while other may think this detracts from a princess cut’s beauty (covering the corners). In the end it’s up to you whether you’re comfortable with this or not.

A round cut has no such issue, in that it has no sharp corners and the girdle is always very well protected by whatever setting there is, be it prong or bezel type. A round cut’s weakness is its culet, which is always protected by the setting.

7. Round cuts have broader flashes of light, princess cuts are splintery

Another thing to consider is what kind of sparkly look you’re going for. A round brilliant has that classic sparkle, with flashes of light and relatively chunky sparkle. This isn’t very noticeable in diamonds under 0.7 carats but it can be noticeable in 1.5 or 2 carat ones. The light is split into larger chunks, as the facets are not the tiniest.

round princess4

Meanwhile the princess cut has thin and long facets, in a chevron shape, and that leads to a more splintery appearance for the sparkle. The facets are longer than that of a round cut, and they don’t seem as weaved together or braided as they do in a round cut. Instead they sit snugly next to each other, almost parallel.

A round cut tends to sparkle evenly through the diamond, while a princess cut tends to have smaller sparkles that seem more concentrated within the middle of the diamond. Not like crushed ice, but not like a regular brilliant cut either. It really is a unique look.

All this being said, we really do need to discuss the similarities between round cuts and princess cuts, because there are a couple of those and they can really matter when making a decision.

Both round cut and princess cuts hide inclusions very well

Both the princess and the round cut are brilliant cuts, with many small facets (as opposed to a step cut). This means they don’t have large window-like facets that let you see into the diamond plainly, it is always a kaleidoscope and it’s both mesmerizing and confusing. When in comes to inclusions, this is a good thing !

All diamonds have a small amount of inclusions in them, some more noticeable than others. With round and princess cuts you could go as low as VVS2 with the clarity and still have a beautiful diamond. If you can, it might still be a good idea to get a diamond with grey or white inclusions as the black ones are harder to hide.

So both cuts can save you money on clarity, compared to something like an emerald cut or an Asscher.

Both princess and round cuts have many variations

All diamonds are cut on one way or another, some some of those cuts and patented and some have dozens of variations. Both the princess and the round cuts have variations a-plenty and it might be incredibly confusing to navigate those. We’re not going to discuss the myriads of diamond cuts available but we will tell you to always be mindful of how a diamond looks in your eyes, regardless of cut style.

A regular princess cut vs a regular round cut won’t be as impressive, but a variation of a princess cut adapted for fire may upstage a traditional round brilliant. So it’s always a good idea to not pay too much attention to the cut name, rather to the light performance of your diamond.