Zinc
The metal that stops steel rusting: most zinc ends up as a thin galvanised coat on cars, roofs and bridges.
Base metals · No. 8
- US critical 2025
- HHI 1,429 · unconcentrated
Scratch a galvanised steel roof and the zinc keeps protecting it, sacrificing itself so the iron does not rust.
Chart: Illustration: Zinc
Where it comes from
Chart: Map of where it comes from
Zinc is mined as sphalerite, a zinc sulfide that usually comes with lead and silver in the same mine. The ore is floated, roasted, leached and electroplated into pure metal.
Three things to know
- In 1991-92 Marc Rich + Co and two producers held over 90% of LME zinc stocks in an attempted corner.
- Zinc ore also yields indium, whose output rose 1675% between 1975 and 2012 as recovery improved.
- Reserves look short at 18 years, but identified resources of about 1.9 billion tonnes are far larger.
The journey
- 1 Sphalerite oreZinc sulfide, often with lead, silver
- 2 ConcentrateOre crushed and floated
- 3 RoastingBurned to zinc oxide calcine
- 4 ElectrowinningLeached and plated as high-grade zinc
- 5 ProductsGalvanised sheet, die castings, brass