The color rust occurs when orange, red and brown are combined. The English term was first coined in 1692. It was termed for the color that results from the oxidation of iron.
On a color wheel, rust is the combination of several hues. Beginning with the primary three colors, mix yellow and blue to make green. Then add red to get brown. Red and yellow can be mixed to become orange. Adding these primary and secondary colors results in rust.
Although traditionally rust is recognized as a reddish color, it can also be brown, orange, yellow and even green in appearance. While commonly used to describe a color for painting and decorating, rust also has added significance in science. When metals, such as rebar, are placed in a chlorine-rich environment, green rust is a result of corrosion in the low-oxygen environment.