Alloy nickel, but are not native to the Earth. One of the first alloys made by humans was bronze, which is a mixture of the metals tin and copper. Bronze was an extremely useful alloy to the ancients, because it is much stronger and harder than either of its components. Steel was another common alloy. However, in ancient times, it could only be created as an accidental byproduct from the heating of iron ore in fires (smelting) during the manufacture of iron. Other ancient alloys include pewter, brass and pig iron. In the modern age, steel can be created in many
Antimicrobial copper-alloy touch surfaces surfaces typically manufactured with standard materials (i.e., plastic, chrome, aluminum) were replaced with copper alloys. These included a copper alloy set of sink tap handles (60% Cu, 40% Zn) and a ward entrance door push plate (70% Cu, 30% Zn). Contamination reductions of 90–100% were observed for "Staphylococcus aureus", "Escherichia coli", "Klebsiella pneumoniae", "Acinetobacter baumanii", "Enterococcus" spp., and "Candida albicans" on the copper alloy surfaces versus the non-copper standard surfaces. A microorganism reduction of 100% was observed on the hot tap copper alloy handle. The high degree of clinical performance suggested that copper alloy surfaces may increase the effectiveness of