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.