See Potosí (disambiguation) for articles sharing the titlePotosí.
POTOSÍ, a department of Bolivia occupying the south-western angle of that republic, bounded N. by Oruro, Cochabamba and Chuquisaca, E. by the two last departments and Tarija, S. by Argentina and W. by Chile and Oruro. Pop. (1900), 325,615, the larger part Indians; area, 48,801 sq. m. The eastern part of the department is traversed north to south by the eastern branch of the Andes, locally known as the Cordillera de los Frailes and the Sierras de Chichas. Spurs and broken ranges project eastward from these, between which are the headstreams of the Pilcomayo and Guapay, the first flowing south-east to the La Plata, and the second north-east to the Madeira and Amazon. The Pilcomayo itself rises in the department of Oruro, but several of its larger tributaries belong to Potosí - the San Juan, Cotagaita and Tumusla in the south, and Cachimayo in the north. The western part of the department belongs to the great Bolivian altaplanicie, or southern extension of the Titicaca basin. It is a barren, saline waste, almost uninhabitable. In the north, bordering on the transverse ridge of which the Cerro de Tahua 07454 ft.) forms a part, is the depression known as the Pampa de Empeza, 12,080 ft. above sea-level, which is largely a region of morasses and saline plains. On and near the southern frontier is another transverse ridge, in part formed by the Sierra de Lipez, and in part by apparently detached groups of high peaks; it is a waterless desert like the Puna de Atacama.
Potosí is essentially a mining department, though agriculture and grazing occupy some attention in the eastern valleys. The western plateau is rich in minerals, especially silver and copper. The Huanchaca group of mines, situated on the slopes of the eastern Cordillera, overlooking the Pampa de Empeza, has the largest output of silver in Bolivia. The Pulacayo mine, belonging to this group, 15,153 ft. above sea-level, ranks next to the Broken Hill mine of Australia in production. Between 1873 and 1901 it yielded 4520 tons of silver, of an estimated value of X23,200,000. Farther south are the Portugalete mines, once very productive, and near the Argentine border are the Lipez mines. East of the Cordilleras are the famous "silver mountain" of Potosí, once the richest silver mine in the world; the snow-capped peak of Chorolque (18,452 ft.), which is claimed to have the highest mine in the world; Porco, a few miles south-west of Potosí; Guadalupe, Colquechaca and Aullagas. Besides silver, the Chorolque mines also yield tin, copper, bismuth, lead and wolfram. In 1907 the national government undertook railways from Potosí to Oruro, 205 m., and from Potosí to Tupiza, 155 m., to connect with the Central Northern line of Argentina, which was opened to Quiaca on the frontier on the 25th of May 1908. In western Potosí the department is traversed by the Antofagasta & Oruro railway (0.75 metre gauge). Besides Potosí, the capital of the department, the principal towns are Huanchaca (pop. about 10,000 in 1904), the seat of famous silver mines, 13,458 ft. elevation, and overlooking the Pampa de Empeza; Uyuni, 9 m. from Huanchaca, 12,100 ft. above sea-level, a small town but an important railway junction and commercial centre on the waterless plain, the shipping point and supply station for an extensive mining region; and Tupiza (pop. about 5000 in 1906), a prettily situated town near the Argentine frontier, on a small branch of the San Juan river, 9800 ft. above sea-level.