Lead and its alloys are among the oldest metallic materials known and used. Although lead is not found in its native state, it is easily extracted from its ores. Easy to melt or work by deformation, it was already in use several millennia ago, as evidenced by the corrosion-proof objects that have come down to us.
World production of refined lead is around 5 million tonnes a year. In 1990, 260,000 t of lead were produced in France, including 136,800 t from ores (1
re
smelting) and 123,200 t from recovered lead materials (2nd smelting).
Industrial production processes are described in the article on lead metallurgy
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. By way of illustration, French standard NF A 55-105 defines six grades of metal, ranging in purity from 99.985% to 99.5%. In fact, most French production is currently made up of 99.985% extra-refined lead, containing a maximum of 150g of impurities per tonne, including a maximum of 50g of impurities other than bismuth.