medieval brass doorknob

Medieval brass doorknob.

Brass is a yellowish or reddish, malleable and ductile alloy of copper (55–95%) and zinc (5–45%), known since Roman times and widely used in industry and for ornament and decoration.


Up to 36% zinc forms α-brass, which can be worked cold; with more zinc a mixture of α and β-brass is formed, which is less ductile but stronger. Brasses containing more than 45% zinc (white brasses) are unworkable and have few uses. Some brasses also contain other metals: lead to improve machinability, aluminum or tin for greater corrosion-resistance, and nickel, manganese, or iron for greater strength.


Brass is widely used for pipe and electrical fittings, screws, musical instruments, and ornamental metal work.