Small additions of Lead in bronze and other copper alloys found at archaeological sites, are believed to have been added as a diluents to the more precious copper, and/or to reduce the melting temperature.

Some modern copper, aluminum and steel alloys use small additions of Lead to improve machinability.

Some aluminum alloys are formulated with a Lead addition of less than 4% for improved machinability. These are mainly used by smaller specialized companies for the automotive industry. The market share of these products is estimated at 0.3% (maximum) of the aluminum used in automotive applications, with a decreasing trend with time.