Brass is a metal alloy made of copper and zinc, the proportions of zinc and copper can be varied to create a range of brasses with varying properties. Brass has higher malleability than bronze or zinc. These varying mixtures produce a wide range of properties and variation in color. Increased amounts of zinc provide the material with improved strength and ductility. Brass can range in color from red to yellow depending on the amount of zinc added to the alloy. If the zinc content of the brass ranges from 32% to 39%, it will have increased hot-working abilities but the cold-working will be limited. If the brass contains over 39% zinc, it will have a higher strength and lower ductility at room temperature.
Aluminium makes brass stronger and more corrosion-resistant. Aluminium also causes a highly beneficial hard layer of aluminium oxide to be formed on the surface that is thin, transparent and self-healing. Tin has a similar effect and finds its use especially in seawater applications (naval brasses). Combinations of iron, aluminium, silicon and manganese make brass wear and tear resistant.