The word "cobalt" comes from the German words "kobalt" and "kobold," meaning "goblin." Miners, who mined this metal, associated the element with this German word because there were superstitions concerning this particular material. In 1735, George Brandt discovered this element when he isolated it.
Although cobalt is not present in nature in pure form, there are some ores that contain it, including cobaltite and erythrite. The refining process of other metals, such as copper and silver, also produce cobalt as a byproduct. Some applications of cobalt are in electroplating, as an alloying agent and a coloring dye used in glass and paint.
Cobalt has the atomic number 27, and its atomic weight is 58.93 grams per mole. Cobalt-60 is a radioactive isotope of cobalt that is useful as a medical treatment for some types of cancer.