Cosmati

The Cosmati were a Roman family, seven members of which, for four generations, were skilful architects, sculptors and workers in decorative geometric mosaic, mostly for church floors. Their name is commemorated in the genre of Cosmatesque work, often just called "Cosmati", a technique of opus sectile ("cut work") formed of elaborate inlays of small triangles and rectangles of colored stones and glass mosaics set into stone matrices or encrusted upon stone surfaces. Bands, panels and shaped reserves of intricate mosaic alternate with contrasting bands, guilloches and simple geometric shapes of plain white marble. Pavements and revetments were executed in Cosmatesque technique, columns were inlaid with fillets and bands, and immovable church furnishings like cathedras and ambones were similarly treated. Initial inspiration for the technique was Byzantine, transmitted through Ravenna and Sicily, while some of the minutely-figured tiling patterns are Islamic in origin, transmitted through Sicily.

In addition, members of the Cosmati engaged in commerce in ancient sculptures, some unearthed in the course of excavating for marbles for reuse. More than one ancient Roman sculpture has survived with the name of one of these craftsmen incised in it.