A diamond shape inspired by a woman’s lips makes for a great royal love story. But the woman at the center of the marquise-cut diamond’s origin story deserves far more than a footnote as King Louis XV’s mistress. Madame de Pompadour was one of the most influential women at the French court — and her relationship with the king continued to shape royal affairs long after their romance ended.
The legend of the marquise diamond dates to about 1745, when Louis XV supposedly commissioned his jeweler to create a diamond resembling the lips of Jean-Antoinette Poisson, the woman who would become the Marquise de Pompadour. The two reportedly met at a masked ball at Versailles, where the king was captivated by her beauty.
He soon made her his official chief mistress and, later that year, bestowed upon her the title Marquise de Pompadour. The elongated outline of the marquise-cut diamond was also known as the navette, or “little ship” in French, a reference to its boat-like silhouette.
The romantic relationship between Louis XV and Pompadour would last about five years, but for the next 14 years, until her death in 1764 at age 42, she retained his trust and became a powerful political confidante, court insider and influential patron of French culture.
She used her position to champion the arts and architecture. She supported artists including French painter François Boucher, helped establish the royal porcelain manufactory at Sèvres and encouraged projects that reflected the elegant Rococo style associated with the era.
She also supported Enlightenment thinkers and writers, helping make the royal court an important center of intellectual and artistic life. Her influence reached well beyond her personal relationship with Louis XV, making her one of the defining cultural figures of 18th-century France.
That legacy makes the marquise diamond’s origin story considerably deeper and more nuanced than a royal sweetheart inspiring a pretty gemstone shape.
And the shape itself remains distinctive nearly three centuries later. A modern marquise is an elongated brilliant-style diamond with curved sides and two pointed ends, typically featuring 58 facets. Its proportions and faceting have evolved considerably since the 18th century as cutters developed a better understanding of symmetry and light performance.
The shape offers a clever visual advantage, too. Because much of the diamond's weight is spread across its elongated outline, a marquise can appear larger face-up than a round diamond of the same carat weight. Its north-south orientation can also create the illusion of longer, more slender fingers.
Symmetry is especially important when choosing a marquise-cut diamond. Uneven curves or misaligned points can be obvious, while a pronounced “bow-tie” — a darker area across the center — can negatively affect its appearance. The pointed tips are also vulnerable to chipping, making protective settings, such as V-prongs, a smart choice.
Today, designers are giving the classic shape a fresh spin by setting marquise diamonds east-west, with the points extending across the finger. Celebrities have embraced both traditional and contemporary versions, including Victoria Beckham, Catherine Zeta-Jones, Portia de Rossi and Selena Gomez.
So while the marquise may have been born from a royal legend about a beautiful pair of lips, its enduring appeal owes something to a far more powerful legacy: the extraordinary woman whose name it carries.
Credits: Photo of 28.3-carat marquise-cut diamond by Chip Clark / Smithsonian and digitally enhanced by SquareMoose. Image of the Marquise de Pompadour by Charles André van Loo, Public domain, via Wikimedia Commons.
