<P> Columbite and Tantalite are ores used to produce the elements niobium and tantalum . Columbite and tantalite are collectively known as coltan in Africa . Tantalum is a valuable rare element used in electronics manufacturing . In Nigeria, pegmatite deposits of coltan are frequently also the source of several precious and semi-precious stones such as beryl, aquamarine, and tourmaline . These pegmatites are found in Nassarawa State near the Jos Plateau, as well as in several areas in southeast Nigeria . There is small - scale mining of these minerals . Wolframite (tungsten) can be found in the North states . </P> <P> Bitumen was first discovered in 1900, with focused exploration beginning in 1905 . Bitumen deposits are found in Lagos State, Ogun State, Ondo State, and Edo State . Conoco has performed a technical and economic evaluation of these deposits, and believes there to be over thirteen billion barrels of oil in these tar sands and bitumen seepages . </P> <P> Nigeria has several deposits of iron ore, but the purest deposits are in and around Itakpe in Kogi State . </P> <P> The National Iron Ore Mining Company was founded in 1979 and given the mission to explore, exploit, process, and supply iron ore concentrate to the Ajaokuta Steel Company (ASCL) in Ajaokuta and Delta Steel Company (DCL) in Aladja . Additional demand has come from several steel rolling mills . The company and its mining operations are based in Kogi State . Export of excess iron ore beyond what is required for domestic needs is currently being explored . Additionally, the Nigerian government has invested in foreign iron ore operations in Guinea. 3 </P>

Iron ore is found in which state in nigeria