Tantalite
Tantalum is a dark blue-gray metal that is dense, ductile, very hard, easily fabricated, and highly conductive of heat and electricity. The metal is renowned for its resistance to corrosion by acids; in fact, at temperatures below 150 °C tantalum is almost completely immune to attack by the normally aggressive aqua regia. Tantalum’s high melting point of 3017 °C (boiling point 5458 °C) is exceeded only by tungsten, rhenium and osmium for metals, and carbon.
The major use for tantalum, as the metal powder, is in the production of electronic components, mainly capacitors and some high-power resistors. Tantalum is also used to produce a variety of alloys that have high melting points, are strong and have good ductility. Alloyed with other metals, it is also used in making carbide tools for metalworking equipment and in the production of super-alloys for jet engine components, chemical process equipment, nuclear reactors, and missile parts.