ELBA (Gr. AlOaXia; Lat. Ilva), island off the west coast of Italy, province of Leghorn, from which it is 45 m. south, and 7 m. southwest of Piombino, the nearest point of the mainland. Pop. (1931) 29,859. It is about 19 M. long, 61 M. broad, and 14o sq.m. in area; its highest point is 3,34o ft. (Monte Capanne) . It forms, like Giglio and Monte Cristo, part of a sunken mountain range extending towards Corsica and Sardinia.
The oldest rocks are schist and serpentine overlaid in the eastern part by Silurian and Devonian beds. The Permian may be represented, but the Trias is absent, and in general the older Palaeozoic rocks are overlaid directly by the Rhaetic and Lias. The Liassic beds are often metamorphosed and the limestones contain garnet and wollastonite. The Eocene shows nummulitic limestone, sandstone and schist; Miocene and Pliocene are ab sent. Serpentines, peridotites and diabases are interstratified with the Eocene deposits; granite, intruded through the Eocene beds, is associated with a pegmatite containing tourmaline and cassiter ite. The celebrated iron ore is of Tertiary age and occurs in differently in all the older rocks. These ores were worked by the ancients. Some of the ore is now dealt with on the island itself, and some at Piombino. The total iron production was 439,000 tons in 1925 (88% of the total for Italy). Granite was quarried by the Romans, but is not now much worked.
Parts of the island are fertile, and cultivation of vines, and tunny and sardine fishery employ part of the population. The capital is Portoferraio—pop. (193r) 11,076—in the centre of the north coast, enclosed by a mountain amphitheatre, the slopes of which are covered with villas and gardens. This is the best harbour, the ancient Portus Argous. The town was built and forti fied by Cosimo I. in 1548, who called it Cosmopolis. Above the harbour, is the palace of Napoleon I., and 4 m. to the south-west is his villa; on the north slope of Monte Capanne is another of his houses. At Le Grotte, between Portoferraio and Rio dell' Elba, and at Capo Castello are Roman ruins.
Elba was famous for its mines in early times, and the smelting furnaces gave it its Greek name of AIOaXia ("soot island"), In 453 B.C. Elba was devastated by a Syracusan squadron. From the i i th to the 14th century it belonged to Pisa, and in came under the dukes of Piombino. In 1548 it was ceded by them to Cosimo I. of Florence. In 1596 Porto Longone was taken by Philip III. of Spain, and retained until 1709, when it was ceded to Naples. In 1802 the island was given to France. On Napoleon's deposition, the island was ceded to him with full sovereign rights, and he resided there from May 5, 1814, to Feb. 26, 1815. After his fall it was restored to Tuscany, and passed with it to Italy in 186o.