The Sahara contains rich mineral resources, of which oil and natural gas are the most important. Hasei R'Mel, Edjeleh, and the Allizi Basin are the main centres of production in Algeria, and the Sarir field is the main source of oil in the Libyan Desert. Other mineral resources in the Sahara found in substantial quantities include iron ore in Algeria and Mauritania, and phosphates in Morocco and Western Sahara.
Traders used to cross the desert by recognized routes linking oases. Major trans-Saharan routes are now at least partially tar-surfaced, with the most commonly used routes running from Beni Abbès (Algeria) to Niamey (Niger) via Bourem (Mali), and from El Goléa (Algeria) to Kano (Nigeria) via the Ahaggar plateau. Bus services run along these routes, with the majority of freight now carried by lorry as opposed to camel. It is also possible to skirt the edge of the desert via Morocco and Mauritania, a route of increasing importance since the sporadic clashes between Tuareg nomads and the Mali and Niger governments in the 1990s.