Niobium
Niobium is a metal element represented by the atomic symbol, Nb. Its atomic weight is 92.9064 and its atomic number is 41. It is a steel-gray, lustrous metal with a melting point of 4,474 ± 50°F (2,468 ± 10°C) and a boiling point of 8,571.2°F (4,744°C). The metal occurs with tantalum in nature and is so similar to it chemically that separation of the two elements is quite difficult.
The naming of an element has seldom involved such controversy as has that of niobium. In 1801, the English chemist Charles Hatchett (1765-1847) came across an interesting mineral in the British Museum. He described the mineral as a "very heavy black stone, with golden streaks" through it. The mineral had been donated to the museum in 1734 by John Winthrop, grandson of the first governor of Connecticut and great-grandson of the first governor of Massachusetts. Hatchett's analysis of the mineral led him to conclude that it contained a new element. He named the element columbium, for Columbia, a romantic name for the United States.
Charles Hatchett was born in London, England, on January 2, 1765, the son of a wealthy coach-builder. He grew up in luxurious surroundings and was a wealthy and successful businessman, as well as a scientist. Hatchett's scientific interests covered a wide range of topics, including the composition of teeth and bones, water chemistry, and mineralogy.
Hatchett's claims for the discovery of columbium were not widely accepted. The great English chemist W. H. Wollaston analyzed columbite and tantalite, and decided that columbium was identical to another recently discovered element, tantalum. Wollaston's view carried the day for nearly a half century. Then, in 1844, the German chemist Heinrich Rose (1795-1864) re-discovered columbium. He showed that it was really different from tantalum and proposed the name of niobium, in honor of Niobe, the daughter of Tantalus in Greek mythology.
For the next century, chemists argued about the correct name of the element. Those in the United States preferred Hatchett's original name of columbium, while European chemists adopted Rose's choice of niobium. In 1950, the International Union of Pure and Applied Chemistry (IUPAC) chose niobium as the official name of the element. Even today, however, both names are in use. Most metallurgists and metal-producers in the United States, for example, continue to use the older name.
Niobium is mined throughout the world with large deposits found in Canada, Brazil, and Nigeria. The primary use for niobium is in alloys. Steel and other alloys to which niobium has been added have superior strength and have been used in airframes and space craft. The metal has found some use also as a "getter" (scavenger) in vacuum tubes. Its ability to become superconductive has inspired research on its possible use in electrical generating systems.
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