Diamond shape guide

Princess Diamond Guide

Modern, square and intensely brilliant.

What makes a good princess diamond?

Look for lively, even brightness rather than a large dead center or obviously uneven light distribution. There is more variation than a simple table/depth chart can capture.

Proportions and face-up size

A near-square ratio is typical, but some stones are slightly rectangular. Compare face-up dimensions because deep stones can carry hidden weight.

Carat is a weight measurement. Use the listed millimeter dimensions to understand how large the diamond will look from the top and to detect stones that carry more of their weight in depth.

Color and clarity

The sharp corners are the vulnerable points. A setting should protect them with appropriate prongs or a bezel-like structure.

For color, compare nearby grades in the same shape and approximate size. The setting metal and the amount of body color your own eye notices are more practical than chasing a grade for status alone.

What to inspect in 360° video

• Whether the diamond stays lively as it rotates rather than going dark for long periods.
• Whether the contrast pattern looks balanced.
• Any central or dark inclusions that remain obvious at normal scale.
• Outline symmetry and whether the shape looks pleasing from straight on.
• For fancy shapes, any bow tie, windowing or uneven brightness.

Loose princess cuts: size and corners

“Princess cut loose diamond” listings look cheap per carat next to rounds. Some of that is real; some of it is depth. A princess can hide a lot of weight below the girdle and look smaller face-up than a well-cut round of the same carat.

• Ratio. Most shoppers want 1.00–1.05 so the outline reads square. At 1.08+ it starts to look like a short radiant.
• Millimeters over carat. Compare width × length. Two “1.00 ct princess” stones can differ by half a millimeter face-up.
• Corners. The four points chip. Budget for a setting that actually covers them (prongs on the points, or a bezel). A loose stone with a report nick on a corner is not a bargain.
• Light. Look for an even, lively square — not a dark cross or a dead center that never lights up in video.

Best buying strategy

1. Set a carat and millimeter-size range.
2. Choose a color range appropriate to the setting.
3. Choose a clarity range, then inspect the actual inclusions.
4. Reject stones with weak visual performance even if the paper grades look attractive.
5. Compare at least three similar candidates side-by-side.

Educational reference: GIA diamond-quality and shape guidance. Fancy-shape appearance varies materially from stone to stone, so ratios and measurements are screening tools rather than guarantees.