HandlingĮxposure to cobalt (metal fumes and dust) should be limited to 0.05 mg/m 3 (8-hour time-weighted average 40-hour week). ![]() IsotopesĬobalt-60, an artificial isotope, is an important gamma ray source, and is extensively used as a tracer and a radiotherapeutic agent. Soils should contain 0.13 to 0.30 ppm of cobalt for proper animal nutrition. Cobalt carefully used in the form of the chloride, sulfate, acetate, or nitrate has been found effective in correcting a certain mineral deficiency disease in animals. A solution of the chloride is used as a sympathetic ink. It is the principal ingredient in Sevre's and Thenard's blue. The metal is used in electroplating because of its appearance, hardness, and resistance to oxidation.Ĭobalt salts have been used for centuries to produce brilliant and permanent blue colors in porcelain, glass, pottery, tiles, and enamels. Stellite alloys, containing cobalt, chromium, and tungsten, are used for high-speed, heavy-duty, high temperature cutting tools, and for dies.Ĭobalt is also used in other magnetic steels and stainless steels, and in alloys used in jet turbines and gas turbine generators. For more information on the Visual Elements image see the Uses and properties section below. Each allotrope has different physical properties. It is alloyed with iron, nickel and other metals to make Alnico, an alloy of unusual magnetic strength with many important uses. Cobalt - Element information, properties and uses Periodic Table Glossary Allotropes Some elements exist in several different structural forms, called allotropes. The transformation is sluggish and accounts in part for the wide variation in reported data on physical properties of cobalt. ![]() Cobalt tends to exist as a mixture of two allotropes over a wide temperature range. It has a metallic permeability of about two thirds that of iron. PropertiesĬobalt is a brittle, hard metal, resembling iron and nickel in appearance. Geological Survey has announced that the bottom of the north central Pacific Ocean may have cobalt-rich deposits at relatively shallow depths in water close to the the Hawaiian Islands and other U.S. Important ore deposits are found in Zaire, Morocco, and Canada. SourcesĬobalt occurs in the minerals cobaltite, smaltite, and erythrite, and is often associated with nickel, silver, lead, copper, and iron ores, from which it is most frequently obtained as a by-product. −3, −1, +1, +2, +3, +4, +5 (an amphoteric oxide)įrom the German word Kobald, goblin or evil spirit also from the Greek cobalos, mine. ![]() Supplimental colbalt is essential in sheep's diets to prevent the sheep disease Swayback, and to improve the wools quality.
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