Lead

Lead is a lustrous metal that is extremely soft, highly malleable and ductile. It is a poor electrical conductor, fairly corrosion resistant, but does tarnish upon prolonged exposure to air. The applications for lead cover a broad scale.

It was originally used by the romans for plumbing, but has been phased out due to environmental concerns over lead poisoning. Similarly it has been used extensively in paints, and as an antiknock compound in petrol. However with increasing awareness over the health hazards involved, its use has been dramatically reduced. The metal provides an extremely effective shield to radiation, and hence is used as a radiation shield around X-ray equipment and nuclear reactors.