Moissanite 101 ยท Shape vs Shape
Moissanite Round vs Princess Cut: Circle or Square?
The classic brilliant against the crisp modern square โ compared on size, fire and the four corners that change how a princess must be set.
Written by the Mapple Gems workshop, Surat ยท Updated 25 September 2026
Short answer
Choose a round moissanite for the most fire, a slightly larger face-up size (6.5 mm against about 5.5 mm at 1 ct DEW) and no corners to protect. Choose a princess cut for a clean, modern square โ but make sure a prong covers each of its four sharp corners, which are the only real weak points on the stone.
Round and princess are both brilliant cuts, so both sparkle. The difference is geometry. A round is a circle with no edges to catch. A princess is a square with four pointed corners, cut deep to hold its weight. That gives it a sharp, architectural look that suits minimal and modern designs โ and a couple of practical requirements a round does not have.
For all ten moissanite shapes compared, see our moissanite shape comparison.
Round vs princess moissanite at a glance
| Round | Princess | |
|---|---|---|
| Face-up at 1 ct DEW | 6.5 mm | about 5.5 ร 5.5 mm |
| Face-up at 2 ct DEW | 8.0 mm | about 7.0 ร 7.0 mm |
| Fire | Highest of any shape | High, a clear step below |
| Must protect | Nothing | Four sharp corners |
| Best prongs | 4 or 6 round claws | V- or L-shaped prongs on each corner |
| Wedding band | Straight usually fits | Straight usually fits |
| Common in bands | Pavรฉ, eternity | Channel-set, eternity |
| Style | Timeless | Modern, geometric |
DEW = diamond equivalent weight. See the moissanite size chart for every size.
Size: the round covers more of the finger
A princess cut is cut deep, so it carries more of its weight below the girdle. At 1 ct DEW its sides measure about 5.5 mm, against a round's 6.5 mm diameter. The princess's corner-to-corner diagonal is longer than its sides, which gives it presence, but its total face-up area is slightly smaller than a round's at the same weight.
If you love the square outline but want more face-up size, a radiant cut โ a square or rectangle with cropped corners โ is worth comparing, and a halo adds visible size to either shape.
Fire: round leads
Moissanite's dispersion is 0.104, more than twice diamond's 0.044, and a round brilliant shows the most of that colour of any shape. A princess cut is also a brilliant, with its own crisp, criss-cross sparkle, but it sits a few places lower in the fire ranking. For someone worried that moissanite looks too colourful, that is a point in the princess's favour; for someone who wants the most rainbow possible, it is a point for the round. Full ranking in moissanite shapes ranked by fire.
From the workshop: on a princess, the corners are the whole story.
Moissanite is Mohs 9.25 and, unlike diamond, has no cleavage planes, so it is a tough stone. But hardness is not toughness. When any stone chips, it chips at a point or a thin edge โ and a princess has four of them. The fix is simple and must be decided before the ring is made: a prong over every corner, ideally V- or L-shaped so it cups the tip rather than sitting beside it. A princess held by prongs on its flat sides, with the corners exposed, is the one build we would always change.
A bezel or half-bezel protects the corners completely and gives a very clean modern look. With that sorted, a princess moissanite is entirely suitable for daily wear.
The wedding band
Both shapes are compact and do not extend along the finger, so a straight band usually sits flush beside either one. Princess cuts are especially popular in channel-set wedding bands, where the stones sit edge to edge between two walls of metal and the corners are fully protected โ a natural match for a princess engagement ring.
How to decide
- Want maximum sparkle? Round.
- Want the largest face-up size for the weight? Round.
- Want a modern, geometric look? Princess.
- Active hands and no wish to think about it? Round, or a bezel-set princess.
- Choosing princess? Insist on a prong over each corner.
- Either way: ask for a rotating video โ no laboratory grades moissanite.
Keep reading
Frequently asked questions
Does a round or princess moissanite look bigger?
The round. At 1 ct diamond equivalent weight a round measures 6.5 mm across, while a princess measures about 5.5 mm per side, because the princess is cut deeper. Its diagonal is longer, but its face-up area is slightly smaller.
Does a princess cut moissanite chip easily?
Not when it is set properly. Its four sharp corners are its only weak points, so each should sit under a V- or L-shaped prong, or inside a bezel. Moissanite has no cleavage planes, which makes it tougher than diamond at the corners.
Which sparkles more, round or princess moissanite?
The round shows the most fire of any moissanite shape. A princess is also a brilliant cut with strong sparkle, but it ranks a few places lower for coloured fire, which some buyers prefer.
What is the best setting for a princess cut moissanite?
Four prongs placed on the corners, ideally V- or L-shaped, or a bezel that surrounds the stone. Avoid settings that hold a princess by its flat sides and leave the corners exposed.
Will a straight band fit a princess cut moissanite ring?
Usually yes. A princess is compact and does not extend along the finger, so a straight band normally sits flush. A channel-set princess band is a popular match.
Circle or square?
Every ring is made to order in our Surat workshop, with every corner protected by design.
Leave a comment