OURO PRETO ("Black Gold"), a city of the State of Minas Geraes, Brazil, 336m. by rail N. by W. of Rio de Janeiro, and abOut 3oom. W. of Victoria, Espirito Santo, on the eastern slope of the Serra de Espinhaco and within the drainage basin of the Rio Doce. Pop. (1890) 17,860; (1900) decreased to 5,400. The city is built upon the lower slope of the Serra do Ouro Preto, a spur of the Espinhaco, deeply cut by ravines and divided into a number of irregular hills, up which the narrow, crooked streets are built and upon which groups of houses form each a separate nucleus. From a mining settlement the city grew as the inequali ties of the site permitted. The rough streets are too steep and narrow for vehicles. The climate is sub-tropical and humid, though the elevation (3,7oo-3,800ft.) gives a temperate climate in winter.
The days are usually hot and the nights cold, the variations in tem perature being a fruitful cause of bronchial and pulmonary dis eases. Ouro Preto has several historic buildings, the more note worthy are the old Government house (now occupied by the school of mines), the legislative chambers, municipal hall and gaol —all fronting on the Praca da Independencia—the old Casa dos Contos (afterwards the public treasury), a theatre (the oldest in Brazil, restored in 1861-62) and a hospital. There are 15 churches
in the city, all dating from more prosperous days. Ouro Preto is the seat of Brazil's leading school of mines.
The city dates from 1701, when a gold-mining settlement was established in its ravines by Antonio Dias of Taubate. The circum stance that the gold turned black on exposure to the humid air (owing to the presence of silver) gave the name of Ouro Preto to the mountain spur and the settlement. In 1711 it became a city with the name of Villa Rica, a title justified by its size and wealth. At one period of its prosperity its population was estimated at 25,00o to 30,000. In 172o Villa Rica became the capital of the newly created captaincy of Minas Geraes, and in 1823 the capital Of the province of the same name under the empire of Don Pedro I. When the empire was overthrown in 1889 and Minas Geraes was reorganized as a republican state, it was decided to re move the capital to a more favourable site and Bello Horizonte was chosen, but Ouro Preto remained the capital until 1898, when the new town (also called Cidade de Minas) became the seat of gov ernment. (See MINAS GERAES.)