How lead is made

More lead now comes from recycling, mostly old batteries, than from the ground.

stations: 6
things upstream: 9
raw sources: 6
steps from the ground: 3

The short version

Lead is made from galena, a lead sulfide. The ore is crushed and floated to a concentrate, which is smelted with coke into crude lead bullion. Zinc is added to pull out silver and gold, other impurities are skimmed off, and the clean lead is cast. In 2014 recycling gave 5.64 million tonnes, against 4.58 million from ore.

Crush the galena ore

Lead ore, mainly galena, is mostly found with zinc ores. It is crushed and ground so the lead mineral is freed from the rock.

Goes in
Lead ore
Float a concentrate

Froth flotation lifts the lead sulfide off the waste rock to give a concentrate that is rich in lead.
Smelt it with carbon

The sulfide is oxidized to lead oxide in a furnace, then reduced to metal with coke or coal gas. Lead bullion collects below a layer of slag that holds the leftovers. Lead melts at only 327.5 °C.

Goes in
Coke
Skim off the impurities

Air, steam or sulfur is blown through the melt in a furnace. Arsenic, antimony, copper and other metals oxidize and float to the top, where they are skimmed away.
Pull out the silver with zinc

Zinc is stirred into the molten lead, in what is called the Parkes process. Silver and gold dissolve into the zinc, which is separated and sent on to recover the precious metals.

Goes in
Zinc
Cast the refined lead

Clean lead is cast into ingots for battery makers and others. For the purest lead, an electrolytic route called the Betts process plates it from an impure anode onto a pure cathode.

End of the lineLead Next it goes into brass, solder, chess set and 3 more.

Worth repeating

Lead was first smelted in the 7th millennium BC, because it is so easily worked and turns up with silver ores.
Interest in silver helped start widespread lead mining in ancient Rome.
Lead from secondary production is indistinguishable from lead made from ore, so the two can be mixed in the same plant.