Mining in Afghanistan is controlled by the Ministry of Mines and Petroleum, which is headquartered in Kabul with regional offices in other parts of the country. Afghanistan has over 1,400 mineral fields, containing barite, chromite, coal, copper, gold, iron ore, lead, natural gas, petroleum, precious and semi-precious stones, salt, sulfur, talc, and zinc, among many other minerals. Gemstones include high-quality emerald, lapis lazuli, red garnet and ruby. According to a joint study by The Pentagon and the United States Geological Survey, Afghanistan has an estimated US$7 trillion of untapped minerals.