Marcasite, (derived from the Arabic word for pyrite), is a common, pale bronze-colored mineral and has been called the "black diamond." Marcasite is a polymorph of pyrite which means that it has the same chemistry as pyrite but that it has a different structure.

Because of its reflective sheen, marcasite was used by the Aztecs as a mirror surface - but women throughout history have prized its distinctive shine in the form of jewelry. Cleopatra was known for wearing marcasite jewelry and Marie Antoinette preferred it to diamonds and pearls. Queen Victoria wore marcasite jewelry rather than diamonds as she mourned the loss of her husband Albert for over forty years.

Marcasite jewelry increased in popularity again during the Art Deco period of the 1920's and 1930's and throughout the 1950's and remains fashionable today.