The princess cut and the round brilliant are two very different diamond personalities. The round is timeless, symmetrical, and optimised for light return. The princess is modern, geometric, and architectural. If you're trying to choose between them for an engagement ring, this guide will help.
Princess cut vs round brilliant at a glance
If you only remember one thing: the round brilliant maximises sparkle and looks slightly bigger for its weight, while the princess cut offers a bold, modern square look for roughly 10–20% less. Round is the safe, timeless classic; princess is the distinctive, better-value alternative for those who love a geometric shape.
What Is a Princess Cut?
The princess cut is a square brilliant-cut diamond with pointed corners and a facet pattern designed to produce high brilliance. It was developed in the 1980s and became one of the world's most popular diamond shapes during the 1990s and 2000s. While its popularity has softened slightly in recent years (in favour of oval and elongated shapes), it remains a genuinely beautiful and distinctive choice.
Sparkle and Brilliance
Both cuts are brilliant cuts — designed to maximise light return. The round brilliant performs marginally better on raw sparkle and fire, thanks to decades of optimisation in its facet arrangement. The princess cut produces a slightly different light pattern: bright and lively, with a cross-like pattern visible in the centre of the stone when viewed from above.
Size Appearance
At the same carat weight, princess cut diamonds appear slightly smaller face-up than round brilliants. This is because a significant portion of the princess's weight is concentrated in its depth. However, the square shape creates a bold visual presence that many find more striking than a round of similar size.
Price Comparison
Princess cut diamonds are generally priced 10–20% less than round brilliants of comparable quality. This is partly because the square cut retains more of the original rough diamond than a round, reducing waste during cutting. For buyers who like the look, this represents genuine value.
Setting Considerations
The pointed corners of a princess cut require prong protection — a standard four-prong setting leaves the corners exposed and vulnerable to chipping. Look for a setting specifically designed for princess cuts, with prongs placed at each corner to protect these thinner points.
Durability and everyday wear
Both stones are diamonds, so both rate a perfect 10 on the Mohs hardness scale and resist scratching. The practical difference is those princess corners: they are the most vulnerable point on the stone and can chip if knocked hard against a hard surface. A round brilliant has no sharp points, so it's marginally more forgiving for very active hands — though a well-designed corner-protecting setting largely closes that gap for the princess.
Which to Choose?
Choose round if you want maximum brilliance, a completely timeless look, and easy quality comparison. Choose princess if you prefer a modern, geometric aesthetic and want to get a slightly bigger-looking stone for your budget.
Explore the full range of diamond shapes available at Una Diamond, all made to order in Australia.
Explore Una Diamond Engagement Rings
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