Lead

Lead is a soft, dense, bluish-gray post-transition metal that tarnishes when exposed to air. It is obtained mainly from galena, a lead sulfide ore, by roasting and smelting; much of today’s supply also comes from recycling, especially spent batteries. Its density and resistance to corrosion make it useful in lead–acid batteries and radiation shielding, and it was once widely used in products such as pipes and paint. Lead is a potent neurotoxin that can damage the brain and nervous system, so its use is restricted in many products.