Niobium is a chemical element with the symbol Nb and atomic number 41. It is a soft, grey, ductile transition metal, which is often found in the minerals pyrochlore and columbite. Niobium has been historically known as columbium, and its former name persists in many scientific fields. It is used in alloys for improved strength and corrosion resistance, and is also used in superconducting magnets. Niobium is also used in welding and cutting, and in the production of electronic components.