Editing Lead (section)

=== On Earth ===
[[File:Lingot de plomb de l'époque romaine. Mines de Cartagène Espagne.jpg|thumb|Lead ingot from Roman times, Cartagena, Spain]]
Lead is classified as a [[Goldschmidt classification#Chalcophile elements|chalcophile]] under the [[Goldschmidt classification]], meaning it is generally found combined with sulfur.{{sfn|Langmuir|Broecker|2012|pp=183–184}} It rarely occurs in its [[native metal|native]], metallic form.{{sfn|Davidson|Ryman|Sutherland|Milner|2014|pp=4–5}} Many lead minerals are relatively light and, over the course of the Earth's history, have remained in the [[Earth's crust|crust]] instead of sinking deeper into the Earth's interior. This accounts for lead's relatively high [[Abundance of elements in Earth's crust|crustal abundance]] of 14&nbsp;ppm; it is the 36th most [[Abundances of the elements (data page)|abundant]] element in the crust.{{sfn|Emsley|2011|pp=286, passim}}{{efn|Elemental abundance figures are estimates and their details may vary from source to source.{{sfn|Cox|1997|p=182}}}}

The main lead-bearing mineral is [[galena]] (PbS), which is mostly found with zinc ores.{{sfn|Davidson|Ryman|Sutherland|Milner|2014|p=4}} Most other lead minerals are related to galena in some way; [[boulangerite]], Pb<sub>5</sub>Sb<sub>4</sub>S<sub>11</sub>, is a mixed sulfide derived from galena; [[anglesite]], PbSO<sub>4</sub>, is a product of galena oxidation; and [[cerussite]] or white lead ore, PbCO<sub>3</sub>, is a [[Chemical decomposition|decomposition]] product of galena. [[Arsenic]], [[tin]], [[antimony]], [[silver]], [[gold]], [[copper]], [[bismuth]] are common impurities in lead minerals.{{sfn|Davidson|Ryman|Sutherland|Milner|2014|p=4}}

[[File:Elemental abundances.svg|thumb|left|upright=1.15|Lead is a fairly common element in the [[Earth's crust]] for its high atomic number (82). Most elements of atomic number greater than 40 are less abundant.|alt=A line chart generally declining towards its right]]
World lead resources exceed two billion tons. Significant deposits are located in Australia, China, Ireland, Mexico, Peru, Portugal, Russia, United States. Global reserves—resources that are economically feasible to extract—totaled 88&nbsp;million tons in 2016, of which [[Australia]] had 35&nbsp;million, China 17&nbsp;million, Russia 6.4&nbsp;million.{{sfn|United States Geological Survey|2017|p=97}}

Typical background concentrations of lead do not exceed 0.1&nbsp;μg/m<sup>3</sup> in the atmosphere; 100&nbsp;mg/kg in soil; 4&nbsp;mg/kg in vegetation, 5&nbsp;μg/L in fresh water and seawater.{{sfn|Rieuwerts|2015|p=225}}