MEXICO CITY, MEXICO—The AFP reports that 17 artifacts have been returned to Mexico by collectors in the Netherlands, who have held the objects for 30 years. The artifacts, all made of clay and dated from A.D. 400 to 1521, were made in areas across Mexico, according to researchers from Mexico’s National Institute of Anthropology and History, who authenticated the items. It is not clear how the artifacts came to be in the possession of the collectors. To read about an Aztec obsidian mirror once owned by a sixteenth-century English polymath, go to "Reflecting the Past."