Niobium is a soft, gray metal that can take on a bluish color when exposed to air. Despite its softness, though, the element has a very high melting point of more than 2,400 degrees Celsius. It becomes harder when impurities are added to it. It has the highest critical temperature of the superconductor elements as well as the largest magnetic penetration depth of any element. When it was first discovered, niobium was confused with tantalum (atomic number 73), which has similar characteristics.
English scientist Charles Hatchett discovered niobium in 1801 after he studied a sample of the element that was found in the United States. For part of the 19th century there was some dispute on the difference between niobium and tantalum. In 1864, scientists Christian Wilhelm Blomstrand and Henri Etienne Sainte-Claire Deville finally designated the differences between the two elements. In 1949, the element's name was officially changed to niobium.
Most of the niobium found today is used to produce steel. Niobium helps strengthen structural steel, which makes it useful in the production of cars and pipes. Because of its high melting point, niobium is also combine with other elements to create superalloys that are used in the space program. Niobium was used in the creation of the main engine of the Apollo lunar modules and other rockets. Niobium is also used in coins, medical equipment and telescopes as a detector for electromagnetic radiation.
While the element was once named for America, the United States no longer produces niobium, instead importing the element from other countries. Niobium is mainly produced Canada, Brazil, Australia, Rwanda, Ethiopia, Mozambique and Burundi. The world's largest deposit is located in Araxá, Brazil in a mine owned by Companhia Brasileira de Metalurgia e Mineração. Niobium is extracted from the earth in open-pit mines and recovered when ores are processed for both niobium and tantalum.