Niobium is a soft, shiny, white, and ductile metal found in pyrochlore, columbite and slag of tin ores. It takes on a bluish cast when exposed to air at room temperatures for a long time. Although frequently found in the same minerals as tantalum, niobium is more plentiful in nature.
Niobium, like tantalum, resists corrosion and maintains good physical properties at high temperatures and has a number of outstanding attributes, including:
• High boiling point (4,744°C, 8,571°F)
• High melting point (2,477°C, 4,491°F)
• Resistance to corrosion
• Ductility, i.e. it alloys well
• Low thermal expansion
• High capacitance