Bras incense burner, Indian, 19th century.
© Science Museum / Science & Society Picture Library
An incense burner, made in the form of a peacock. Bras is an alloy of copper and zinc. Bras which contains a proportion of les than 36% zinc is ductile when cold and can be easily worked into complex shapes. A proportion of zinc greater than 36% makes a harder and stronger alloy. The earliest bras was made by the Ancient Greeks, probably around 330 BC, but the Romans were the first to produce the alloy in any quantity.