Phosphor Bronze Sheet: Bronze Deoxidised with Copper Phosphide and Rolled

Phosphor bronze is bronze cleaned of its oxide by a little phosphorus: it casts sound, keeps a bright surface when molten and rolls cold into tough, springy sheet. Brannt (1889) makes the phosphorus carrier, copper phosphide, from superphosphate, copper and coal in a crucible, then drops small pieces of it into the bronze melt. The picture: an acoustic guitar string, steel wrapped in phosphor bronze wire, one of the alloy's best-known uses.