Copper than less-developed countries (30–40 kg per capita). The process of recycling copper is roughly the same as is used to extract copper but requires fewer steps. High-purity scrap copper is melted in a furnace and then reduced and cast into billets and ingots; lower-purity scrap is refined by electroplating in a bath of sulfuric acid. Numerous copper alloys have been formulated, many with important uses. Brass is an alloy of copper and zinc. Bronze usually refers to copper-tin alloys, but can refer to any alloy of copper such as aluminium bronze. Copper is one of the most important constituents of
Tin a desirable tonal resonance. When a tin/lead alloy cools, the lead cools slightly faster and produces a mottled or spotted effect. This metal alloy is referred to as spotted metal. Major advantages of using tin for pipes include its appearance, its workability, and resistance to corrosion. The oxides of indium and tin are electrically conductive and transparent, and are used to make transparent electrically conducting films with applications in Optoelectronics devices such as liquid crystal displays. Punched tin-plated steel, also called pierced tin, is an artisan technique originating in central Europe for creating housewares that are both functional and decorative.