Unknown Roman, ‘Marble portrait head of the Emperor Constantine I’, ca. A.D. 325–370, The Metropolitan Museum of Art

Late Imperial, Constantinian; 1100 lb. (499 kg)
http://www.metmuseum.org/art/collection/search/252884

Image rights: The Metropolitan Museum of Art (Bequest of Mary Clark Thompson, 1923), licensed under CC0 1.0 Universal

About Unknown Roman