?letaliic vanadium does not occur in nature. Over 70 vanadium minerals are known, carnatite and vanadinite being the most important from the point of view of mining. Production of vanadium is linked with that of other metals such as iron, uranium, titanium, and aluminium. As rich minerals rarely occur in large deposits, ores with a low vanadium content, which exist in large amounts, are important. Extraction of vanadium from fossil fuels, including vanadium-rich oil and coal, tars, bitumens, and asphaltites, is important in several countries.