A type of geometrical decorative inlaywork using coloured marbles and mosaic that flourished mainly in Rome between c.1100 and c.1300. The term derives from the Cosmatus family, several members of which are documented as creating such work. At one time it was believed they were responsible for all of it, but it has now been established that many other craftsmen were active in this field, some of them belonging to families whose work extended over several generations. Cosmati work was used to adorn church furnishings such as tombs and pulpits and also for architectural enrichment and floors. Several examples are in Westminster Abbey, executed by imported Italian craftsmen.