Sudan was not rich in mineral resources, and the mineral sector has traditionally made a negligible contribution to the economy, although rising production of gold and crude petroleum in recent years has substantially increased the sector's influence. In 1999, manufacturing and mining accounted for 10% of GDP, which grew by 5.3% in 2001, 9.7% in 2000, 7.7% in 1999, and 6% in 1998. Gold accounted for 7% of the value of exports in 1999, and less than 3% in 2001. Mineral production in 2001 included salt, 120,000 tons (72,211 in 1998); mine chromite, 20,500 tons (gross weight), down from 48,000 in 1999; gold, from the Red Sea Hills, 5,800 kg, up from 4,554 in 1997 (excluding artisanal output); gypsum, 4,000 tons; and cement, 146,0000 (230,600 in 1999, and 380,000 in 1996, a decline resulting from a lack of spare parts). In addition, Sudan presumably produced clay and/or shale for cement, limestone for cement, lime, construction aggregate and fill, other construction materials (clays, sand and gravel, and stone), and marble for export. Other minerals produced were asbestos, manganese, and mica, the latter two in the Red Sea Hills. Sudan was also known to have deposits of barite, copper, iron ore (large reserves near Port Sudan), kyanite, lead, nickel, silver, tungsten, wollastonite, and zinc; however, little change was expected, because of civil unrest.