Floor mosaics in the central nave of the Lateran Archbasilica in Rome. The mosaics are the so-called Cosmati style mosaics.

The Cosmati were a family of artists and craftsmen who lived in Rome from the 12th to the 14th centuries specialising in mosaics. They were named after their founder, a craftsman named Cosimo, who worked in the late 12th century. The Cosmati family’s contribution to the art of mosaic making is significant, as their style influenced the development of mosaic work throughout Europe during the medieval period.

The Cosmati family is best known for their distinctive style of geometric mosaic work, which became known as the “Cosmati style”. Cosmati style mosaics are characterized by their intricate patterns and the use of different types of colored stones, including marble, porphyry, and other precious stones. The mosaics often include geometric shapes, such as circles, squares, and triangles, arranged in intricate patterns. The designs are often divided into compartments or panels, each with its own pattern.

Cosmati style mosaics were also used in the decoration of tombs and other funerary monuments. The tomb of Pope Clement IV, located in the Basilica of Santa Maria in Trastevere in Rome, features a Cosmati-style mosaic panel that depicts the pope in a medallion surrounded by a geometric pattern of colored stones.