Cadmium (Cd)

Cadmium is a soft and silvery-white metal, chemically similar to Zinc and Mercury. Like Zinc, it shows oxidation in most of its compounds, and like Mercury, it has a low melting point. The average concentration of this metal in Earth’s crust is between 0.1 and 0.5 parts per million. It was discovered in 1817 in Germany, as an impurity in Zinc carbonate. Unlike most other metals, Cadmium is resistant to corrosion and is used as a protective coat on other metals.

PRODUCTION & USE

Cadmium occurs as a minor component in most Zinc ores and is a byproduct of Zinc production. It was used for a long time as a corrosion-resistant plating on steel, and its compounds are used as red, orange and yellow pigments, to colour glass and stabilise plastic. Cadmium use is generally decreasing because of its toxicity, and Nickel-Cadmium batteries have been replaced with Nickel-metal hydride and Lithium-ion ones. One of its few new uses is in Cadmium Telluride solar panels.