Uranium dominated Niger's mining sector, ranking it third in the world in production and fifth in reserves. Uranium mining was the country's leading industry in 2002, and uranium was the leading export commodity, accounting for 41% of exports in 1999. A uranium boom occurred in the late 1970s, but with the reduction in world demand in the 1980s, prices fell, although the government was partly protected by contracts negotiated earlier. Cement, brick, and chemical production were other leading industries, and Niger also produced clays, bituminous coal, gold, gypsum, limestone, molybdenum (in connection with uranium ore), phosphate rock, salt, sand and gravel, stone, cassiterite tin, and tungsten (and, at times, columbite, in connection with cassiterite).
Although uranium was the only mineral to be significantly developed, Niger was rich in a number of other minerals. The country's first gold mine, the Samira Hill open pit, was opened in 2000 by Niger's prime minister, and intended to produce 10,000 tons per day of ore. The combined reserves of Samira Hill and the nearby Libiri deposit were 10.1 million tons (2.2 grams per ton of gold). There were some natron and sodium sulfate deposits, an estimated 650 million tons of iron ore deposits at Say, near Niamey, and 400 million tons of phosphate deposits in "W" National Park, in the Niger River Valley. There were also unexploited deposits of manganese, lithium, copper, zinc, lead, silver, cobalt, kaolin, feldspar, gypsum, limestone, marble, and clay.