Emerald cut.

Emerald is a rectangular step-cut. Instead of the triangular facets of brilliant cuts, it has long parallel facets that act like mirrors — light reflects in broader, slower flashes (the "hall of mirrors" effect). It does not sparkle the way a round or oval does. It glows.

Step-cut faceting shows inclusions clearly. A small SI1 inclusion that would be invisible in a round brilliant might be obvious in an emerald cut. Buy VS1 or higher for emerald cuts; SI grades are risky unless you've seen a high-resolution video.

Pricing 20-25% below round. The combination of distinctive look and lower price makes emerald popular with vintage-art-deco fans.

Best in clean, sharp settings — solitaires, three-stone mounts. Emerald cuts struggle in busy halo settings.