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'''Lead''' (pronounced "led") is a [[chemical element]]; it has [[Chemical symbol|symbol]] '''Pb''' (from [[Latin]] {{lang|la|plumbum}}) and [[atomic number]] 82. It is a [[Heavy metal (elements)|heavy metal]] that is [[density|denser]] than most common materials. Lead is [[Mohs scale|soft]] and [[Ductility|malleable]], and also has a relatively low [[melting point]]. When freshly cut, lead is a shiny gray with a hint of blue. It [[tarnish]]es to a dull gray color when exposed to air. Lead has the highest atomic number of any [[stable nuclide|stable element]] and three of its [[isotope]]s are endpoints of major nuclear [[decay chain]]s of heavier elements.
▲ [[post-transition metal]]. Its weak metallic character is illustrated by its [[Amphoterism|amphoteric]] nature; lead and [[lead oxide]]s react with [[acid]]s and [[base (chemistry)|bases]], and it tends to form [[covalent bond]]s. [[Lead compounds|Compounds of lead]] are usually found in the +2 [[oxidation state]] rather than the +4 state common with lighter members of the [[carbon group]]. Exceptions are mostly limited to [[Organolead chemistry|organolead compounds]]. Like the lighter members of the group, lead tends to [[catenation|bond with itself]]; it can form chains and polyhedral structures.
Since lead is easily extracted from its [[ore]]s, prehistoric people in the Near East [[metals of antiquity|were aware of it]]. [[Galena]] is a principal ore of lead which often bears silver. Interest in silver helped initiate widespread extraction and use of lead in [[ancient Rome]]. Lead production declined after the [[Fall of the Western Roman Empire|fall of Rome]] and did not reach comparable levels until the [[Industrial Revolution]]. Lead played a crucial role in the development of the [[printing press]], as [[movable type]] could be relatively easily cast from lead alloys.{{sfn|Theodore Low De Vinne|1899|pp=9–36}} In 2014, the annual global production of lead was about ten million tonnes, over half of which was from recycling. Lead's high density, low melting point, [[ductility]] and relative inertness to [[Redox|oxidation]] make it useful. These properties, combined with its relative abundance and low cost, resulted in its extensive use in [[construction]], [[plumbing]], [[Lead-acid battery|batteries]], [[Bullet|bullets]], [[Shot (pellet)|shots]], [[Mass|weights]], [[solder]]s, [[pewter]]s, [[fusible alloy]]s, [[lead paint]]s, [[Tetraethyllead|leaded gasoline]], and [[lead shielding|radiation shield]]ing.
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