Cadmium is a bluish-white metal which is toxic.  It is soft and similar to zinc. Cadmium is noncorrosive and therefore acts as a protective coat when deposited on other metals.  It is also used in nickel plating as deoxidizer, and also for engraving process. Cadmium colors are used by artists for range of colours from pale yellow to orange. Cadmium colors supplant chrome colours. Cadmium Yellow, Cadmium Orange and Cadmium Scarlet are categorized as semi opaque and opaque colors which has the characteristic of blocking light from passing through water colour paper. This gives a dull look to the color because the light bounces off the color pigment.