The Lily Cut is a modified brilliant cut characterised by a four-pointed outline that resembles a stylised lily or fleur-de-lys when viewed face-up. The cut is most commonly seen in fancy yellow diamonds and in coloured stones intended for high-design jewellery, where its distinctive silhouette differentiates the finished piece from the standard repertoire of round, princess, cushion, and emerald shapes. The cut is sometimes referred to in the trade as a four-point star cut, though the Lily designation is more specific to particular cutter trademarks.

Geometry and faceting

The Lily Cut presents a square-based outline with four pronounced curved indentations between the corners, producing four lobate petals at the cardinal positions. The crown is faceted in a modified brilliant pattern, generally with a small square or octagonal table and a graduated arrangement of star, bezel, and upper girdle facets adapted to the curved outline. The pavilion typically carries a modified brilliant arrangement of main and break facets, with careful attention to the angles at the petal points, where total internal reflection is most likely to fail.

Achieving uniform light return across all four petals is the principal cutting challenge. The acute geometry at each petal tip narrows the optical aperture and tends to produce extinction unless the pavilion is faceted with petal-specific main angles. Skilled lily cutting therefore involves more facets than a comparable princess cut, often in the range of 65 to 80 facets total, and requires a more individualised approach than mass-produced shapes.

Origins and trademark issues

The Lily Cut as a named diamond cut is associated with several proprietary cutter trademarks introduced during the late 1990s and 2000s by individual cutting houses seeking branded fancy shapes. As with many proprietary cuts, the underlying geometry is not protected by patent (cut shape itself is generally not patentable in major jurisdictions) but the name and specific facet count may be trademarked. Buyers should distinguish between a Lily Cut sold under a specific cutter's trademark, which carries documentary backing, and a generic four-petal modified brilliant marketed under the same name by an unaffiliated seller.

Use in finished jewellery

The Lily Cut performs best in solitaire settings and in centre-stone designs where its outline is unobstructed. Its silhouette suits Art Nouveau-revival and modern botanical designs, and it pairs well with coloured stones in yellow, pink, and green hues that reinforce the floral allusion. The cut is less suited to channel-set or pavé applications, where the petal points create setting difficulties.