Long before concrete made its appearance on the building scene in Rome, the Romans utilized a volcanic stone native to Italy called tufa to construct their buildings. Although tufa never went out of use, travertine began to be utilized in the late 2nd century B.C.E. because it was more durable.
rauschenberg merged the realms of kitsch and fine art, employing both traditional media and found objects within his "combines" by inserting appropriated photographs and urban detritus amidst standard wall paintings.