COBALT By Hart Mechlin

Discovery of Cobalt Cobalt has been known for centuries particularly for the distinctive blue color it gives to glass. Cobalt has been used since as early as Pompeii (79 AD) to achieve a deep blue colored glass. In 1735 cobalt was isolated and regarded as an element by Swedish chemist Georg Brandt Brandt discovered cobalt in an effort to discern what element was responsible for the rich blue color in certain glass; before cobalt it was believed to be bismuth. Cobalt Glass Georg Brandt “Cobalt” comes from the German word for goblin, “Kobold,” as well as the Greek word for mine, “Cobalos.”

Elemental Characteristics High strength, high toughness metal Resistant to corrosion and oxidation High melting point; strong under high temperatures Cobalt is a lustrous, tough, silver-blue transition metal Density 8.9 g/cm3 Melting Point 1495°C Boiling Point 2870°C Atomic Mass (Avg.) 58.9332g

Sources of Cobalt Ores containing Cobalt: - Co3S4 (Linnaeite) - CoAsS (Cobaltite) - CoAs2 (Smaltite) Ores are roasted to obtain various metals including Co, Ni, Pb Cobalt is also a byproduct of the productions of iron, nickel, and lead Common Cobalt Ore Cobalt deposits found in Zaire, Australia, Russia, and Canada Cobalt is also present in meteors

Uses for Cobalt Used in creation of superalloys, which are used in gas turbine aircraft engines Used for magnets Combines to create: high speed steels; corrosion and oxidation resistant metals; hardmetals for diamond tools (cemented carbides) Catalysts for petroleum and chemical industries Cobalt-60 is an artificial isotope of cobalt. It has various uses in medicine, involving sterilization of equipment, use as a radioactive power source, and also use as a radiation source in medical radiotherapy for cancer. Cobalt Magnets

VEGEMITE

Bohr-Rutherford Diagram Atomic Number: 27 Valence Electrons: 2

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