Its area is 10,148 km². Its population is 483,792 (2005), of whom about 30% live in the capital, and its population density is 47.67/km². It contains 79 municipalities.
The economy is based on agriculture and mining. The famous Rio Tinto mines have been worked since before 1000 BC, and were the major source of copper for the Roman Empire. As an indication of the scope of ancient mining, sixteen million tons of Roman slag have been identified at the Roman mines. British companies resumed large-scale mining in 1873; the district is the namesake of the Rio Tinto Group.