Princess Cut Diamond
The princess cut is the square brilliant: a crisp, modern shape with plenty of sparkle and a friendlier price than a round of the same weight. This guide covers how it compares, and how to keep its corners safe.
Key Takeaways
- A princess cut is a square brilliant diamond. On GIA reports it's described with a modified brilliant facet arrangement. It gives a sharp, modern, geometric look with strong sparkle.
- It usually costs less per carat than a round of similar weight, mainly because cutting one wastes far less of the rough crystal.
- A round brilliant returns more light and out-sparkles a princess overall, but the difference is smaller than most people expect.
- The four pointed corners are the weak spot. They can chip. A setting that covers them, such as V-prongs or a bezel, is not optional.
- Look for a length-to-width ratio of 1.00 to 1.05 for a stone that reads as a true square.
What is a princess cut diamond?
A princess cut is a square diamond cut for brilliance, using the same light-bouncing, triangular-and-kite facet style you find in a round, just arranged in a square outline. The GIA describes it as a modified brilliant cut, which separates it from step cuts like the Asscher that use long parallel facets and give a quieter, hall-of-mirrors look. The princess arrived relatively recently for a diamond shape, patented in 1980, and it's been one of the most popular square cuts ever since.
Turn one over and it looks like an upside-down pyramid, with a lot of its weight carried down in the pavilion (the bottom). One practical result of that depth: a princess can face up a touch smaller than a shallower shape of the same carat weight, because some of that weight is hidden underneath rather than spread across the top.
Why people choose it
The appeal is the look first. Clean corners, straight edges, a geometric feel that suits modern and slightly architectural ring designs. It's the square that still throws real fire, so you're not trading sparkle for shape the way you do with some step cuts.
Then there's value. When a cutter shapes a round, a large share of the rough crystal is ground away. A princess keeps far more. In fact, two princess cuts can often come from a single piece of rough with relatively little loss. Less waste means a lower price per carat, so the same budget often buys a noticeably larger stone in a princess than in a round. If size-for-money matters to you, that's the headline.
Princess vs round: price and brilliance
This is the comparison most buyers actually care about, so here it is side by side.
| Factor | Princess cut | Round brilliant |
|---|---|---|
| Outline | Square, sharp corners | Circular |
| Sparkle | Strong, with flashes of fire | The benchmark, returns the most light |
| Price per carat | Lower | Higher |
| Rough crystal used | High yield, little waste | Lower yield, more waste |
| Weak point | Four pointed corners | No exposed points |
| GIA cut grade on report | No (polish & symmetry only) | Yes, full cut grade |
On brilliance, the round wins. Its facet pattern is engineered to return light better than any other shape, and it's the most popular shape in diamond jewellery. A princess sparkles well, just not quite at that level. One detail worth knowing: GIA gives round brilliants a full cut grade but does not assign one to fancy shapes like the princess, so for a princess you lean harder on symmetry, polish, and your own eyes (or ours, on the bench) to judge how it performs.
On price, the princess wins, for the cutting-yield reason above. So the honest summary is simple. Want the most sparkle and don't mind paying for it, go round. Want a modern square and more carat for the money, go princess. If you're still weighing options, our Diamond Shapes Guide: Every Cut Compared lays every shape out next to each other, and the Round Brilliant Cut Diamond page covers the round in full.
The corners: the one thing you can't ignore
A princess has four sharp points, and a point is the most fragile thing on a faceted stone. There's no culet (the tiny flat facet at the bottom of a round) to spread the stress, and the GIA notes the pavilion point is susceptible to chipping if it's left exposed. A diamond is extremely hard but it is not unbreakable. A knock at exactly the wrong angle on an unprotected corner can chip it.
The fix is the setting, and it's a standard, well-understood one. The GIA recommends four-prong or bezel settings to protect the corners. In practice that usually means V-shaped prongs that wrap each corner like a little cap, or a bezel that surrounds the whole stone in metal. On our Coquitlam bench we won't set a princess without the corners properly covered. It's the difference between a ring that lasts and one that comes back chipped. If you're planning a build, our Custom Engagement Ring Guide walks through setting choices in detail.
What to look for when buying one
Shape ratio
For a stone that reads as a clean square, aim for a length-to-width ratio between 1.00 and 1.05. The GIA defines a square princess as a ratio not exceeding 1.05:1; push past that and it starts to look rectangular. Past 1.10 or so it's really a different look entirely.
Symmetry
Because there's no GIA cut grade to lean on, even sides and matched corners matter more here. Uneven proportions show up as a stone that just looks slightly off, even if you can't name why.
Clarity near the corners
An inclusion sitting right at or near a corner point is worth avoiding, since that's the spot already carrying the most stress. We'd rather see a clean corner than a clean centre.
If the square look appeals but you'd like the corners softened, two relatives are worth a look: the Cushion Cut Diamond trades sharp corners for rounded ones and a softer sparkle, and the Oval Cut Diamond drops corners entirely while still looking larger for its weight.
Frequently Asked Questions
Is a princess cut cheaper than a round diamond?
Usually, yes, per carat. A princess cut wastes far less of the rough diamond crystal than a round does, so cutters get more finished stone out of every piece of rough, and that saving shows up in the price. For the same budget you can often get a larger princess than round.
Does a princess cut sparkle as much as a round?
Not quite. A round brilliant is the benchmark for returning light and out-sparkles a princess overall. But a princess is still a brilliant-style cut with plenty of fire, the gap is smaller than most people assume, and the square outline is a big part of its appeal.
Do princess cut diamonds chip easily?
The four pointed corners are the vulnerable spot, and the GIA notes the unprotected pavilion point can chip. Set properly, with V-prongs that cap the corners or a bezel that surrounds the stone, a princess holds up well to everyday wear. The setting is what matters.
What length-to-width ratio is best for a princess cut?
For a true square look, 1.00 to 1.05. The GIA defines a square princess as a length-to-width ratio not exceeding 1.05:1. Higher than that and the stone starts to read as rectangular rather than square.
Why doesn't a princess cut get a GIA cut grade?
GIA assigns a full cut grade to round brilliants but not to fancy shapes like the princess. On a princess report you'll get polish and symmetry grades instead, so judging light performance relies more on symmetry, proportions, and seeing the stone in person.
Can you see a princess cut diamond in person in Coquitlam?
Yes. We're an independent family studio in Coquitlam with an on-site goldsmith, so you can compare a princess against a round in the hand and we'll set it with proper corner protection. We design and build the ring here rather than ordering it in.