In 2001, mining and quarrying accounted for less than 1% of GDP, which grew by 6.5%, spurred by postwar rebuilding efforts. Eritrea produced basalt, cement, common clay, kaolin, coral, gold, granite, gravel, gypsum, laterite, lime, limestone (for other than cement), marble, pumice, quartz, salt, sand, and silica sand. The country also had known resources of chromium, copper, magnesium, zinc, lead, silver, barite, feldspar, talc, asbestos, iron ore, nickel-chromite, potash, and potassium. Nevsum Resources Ltd. planned to drill for diamonds at Enjahai. Marine salt was produced at Massawa and Assab. Quarries for limestone, clay or shale, and gypsum were located near Massawa. Artisanal gold production, extracted over a large area in the southwestern hills, was 270 kg in 2001, down from 612 in 1997. Production totals for 2001, in tons, included basalt, 129,000, down from 251,991 in 1999, 403,219 in 1998, and 509,300 in 1996; granite, 128,000, down from 249,829 in 1998; marble, 105,000, down from 200,000 in 1999; and sand, 1.08 million, down from 2.17 million in 1998. The outlook for Eritrea's mineral industry was for gradual recovery from the war, with demand for basalt, granite, gravel, limestone, marble, and sand likely to increase.