PL 18K 18K 18K 9K 9K 9K PA PL 18K 18K 18K 9K 9K 9K PA Length: 4.37mm Length: 4.37mm Width: 4.35mm

A Guide to Square Shaped Diamonds

A Guide to Square Shaped Diamonds

March 22 2023

There is no such thing as a square diamond. Sure, there are lots of diamonds that are square-shaped. But if you asked any diamond jeweller for a square diamond, the most likely reply you’ll get is, “What type?”

There are square squares, round squares, octagonal squares, and rectangular squares - it’s enough to make you question your whole understanding of the word ‘square’. And what’s more, none of these square diamond styles is called ‘Square Cut Diamonds’. That would be too easy.

But don’t let that put you off. Square diamonds - as we’ll discover - are well worth a look. It just might help to know what you’re looking at. So, with that in mind, here’s our guide to all the diamond shapes that are square or square-ish or square-curious or not-square-but-could-be.

But first, this:

Why Choose a Square Cut Diamond?

Approximately 75% of all diamonds sold are Round Brilliant. This means that, by considering a square diamond style, you’re already setting yourself apart from the crowd.

What’s more, there is only one type of round diamond but there are at least three different square diamonds - five if you include diamond shapes with square potential. And, though it might be hard to believe, each of these five square-shaped diamonds has a completely different look, feel and character. It’s fun to choose a diamond shape that’s the perfect match for your or your loved one’s personality.

Square diamonds are also more versatile than round ones when it comes to the setting. Try rotating a round diamond 45 degrees and you’ll see what I mean. Setting a square diamond at a 45-degree angle on a ring or pair of earrings is a really simple way of creating a unique look.

Finally, carat for carat, the fancy square-shaped diamonds generally cost less than Round Brilliants. So by going square, you can save money or - even better - afford a bigger stone!

The only question that remains is, which square shape diamond will you choose?

Princess Cut Diamond

Beautiful and cultured, with corners that can take a man’s eye out.

The Princess Cut is probably the only true square of the lot, as it’s the only one with real corners. This shape is crisp and cool, yet thanks to the Brilliant cut it sparkles just as much as a Round. It’s the ideal choice for someone who wants maximum sparkle with a contemporary look.

Quality Diamonds Tip: The Princess cut’s look is crisp perfection, so aim for as close to square as possible - that is, look for a diamond with a length-to-width ratio between 0.98 and 1.02, ideally 1.00.

Read more in our blog about Princess Cut Diamonds.

Asscher Cut Diamond

Me? Square? Please, dahling, I'm clearly octagonal.

For something a little more ‘cutting edge’, take a look at the Asscher. For starters, it’s the only diamond shape with a designer label. The good news is, that the design is no longer patented so you don’t have to pay a premium for it.

Asscher diamonds have a strong aesthetic, with step-cut detailing that creates a vintage, geometric look. The corners are extremely clipped, giving the stone a striking, almost-octagonal appearance. This is certainly a diamond that will turn heads.

Quality Diamonds Tip: To show off your Asscher at its best, choose a setting that won’t hide those corners (or lack of them).

Read more in our blog about Asscher Cut Diamonds

Cushion Cut Diamond

Don’t you just want to cuddle up next to it?

The Cushion cut takes the hard square form and turns it into a lovely, plump, pillowy….er, cushion. The corners are rounded and the sides slightly curved, so it has a unique ‘soft’ appearance that no other diamond shape can match. It almost feels wrong to call it square. Everything about the Cushion cut oozes romance and loveliness - which is why it’s still going strong more than a century after it first made an appearance.

Quality Diamonds Tip: The Cushion cut has large facets which allow traces of colour and inclusions to show up more than usual, so choose a high colour and clarity grade to ensure a clean look.

Read more in our blog about Cushion cut Diamonds

Honorary Squares

While Princess, Asscher and Cushion cuts are the only ‘real’ square diamond shapes, Emerald and Radiants are square enough that neglecting to mention them would be a crime against diamond-kind…

Radiant Cut Diamond

No autographs, please - Ms Radiant is working.

The name says it all - this is a diamond that lights up the room. With a Radiant cut, you get the best of both worlds: a sleek, sophisticated step cut overlaid with a sparkling Brilliant cut. The result? A show-stopping, big-hitting, Broadway-bound star of a diamond that’s more multi-faceted than Meryl Streep. Grab yourself a Radiant cut that’s square instead of rectangular and you’ve got a real winner.

Quality Diamonds Tip: With a lot of facets squeezed into every stone, colour can become intensified in the Radiant - especially in the clipped corners. Choosing a G-colour grade or higher should take care of this.

Read more in our blog about Radiant Cut Diamonds

Emerald Cut Diamond

It’s not an emerald, it’s a long square diamond

Normally found in rectangular form, it is possible - though not common - to find Emerald cut diamonds with a square ratio. Like Asscher's, Emerald diamonds are step-cut, which gives them their sophisticated Art Deco look. But whereas Asscher's emphasise the triangular, Emerald cut diamonds give you large, open rectangular facets which offer a glacier-like aspect.

Quality Diamonds Tip: With those open facets, clarity becomes crucially important. Make sure you buy a diamond that’s ‘eye-clean’ or opt for a VS2 Clarity grade to be on the safe side.

Read our blog about Emerald Cut Diamonds




Did you know, we can help you create your own bespoke jewellery featuring your favourite square-cut diamond, so click here to find out more.

Our Diamond Experts are available if you'd like to know more about square-cut diamonds, so feel free to contact us here.

Looking for more inspiration, why not follow us on Instagram @QualityDiamonds

  • Ethically Sourced Diamonds
  • Handmade in the UK
  • FREE Shipping Worldwide
  • 60 Day Returns