Why we need cobalt
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Abstract The use of cobalt as a colour for glass can be traced back to about 2600 B.C. in Egypt, but it was not until the mid-nineteenth century that it was isolated as a metal or until the early twentieth century that it was used in metallurgical applications. With few exceptions cobalt is obtained as a byproduct of the winning of another metal, mostly nickel or copper, which has meant that supplies have always been largely dependent on nickel or copper production. In spite of this dependence, cobalt has always commanded a strong position in the marketplace on account of its unique properties. These properties have led to a wide range of specialist applications for the element and its compounds, with the consequence that over the past five years several operations have been developed that will commence production of cobalt or cobalt compounds as primary products in the very near future. The unique properties of cobalt that account for its use in specialist applications are discussed, together with attempts to substitute it with alternative materials. The necessity for cobalt was admirably illustrated in 1979 following the so-called 'Shaba incident' in Zaire, when fears of severe supply disruptions caused the price to rise from about $U.S.5.00/lb to $U.S.40.00/lb in a few months. Over the next few years this situation resulted in massive substitution in applications for which suitable alternative materials are available. Since then the demand for cobalt has been relatively insensitive to its price as its use has been restricted to specialist applications, such that demand has risen even in times of relatively large price increases. Today, demand is strong and is expected to increase steadily over the next five years