Chromium
The element that makes stainless steel resist corrosion; mined mostly in South Africa, smelted into ferrochrome mostly in China.
Steel & alloying · No. 15
- US critical 2025
- HHI 3,340 · highly concentrated
Add at least 10.5% chromium to steel and it grows a self-healing skin that stops rust: stainless steel.
Chart: Illustration: Chromium
Where it comes from
Chart: Map of where it comes from
Nearly all chromium comes from chromite, found in layered igneous rocks such as South Africa's Bushveld Complex and Zimbabwe's Great Dyke. South African mining is moving ever deeper underground.
Three things to know
- Chromite resources top 12 billion tonnes, enough for centuries, but 95% sit in Kazakhstan and southern Africa.
- Nothing can replace chromium in stainless steel or superalloys.
- Ferrochrome smelted on Swedish hydro and nuclear power emitted 1.92 t CO2e per tonne, a third of fossil-powered plants.
The journey
- 1 Chromite oreFrom layered igneous rock, often deep underground
- 2 ConcentrationCrushed into lumpy ore and fines
- 3 SmeltingElectric furnaces make ferrochromium
- 4 Stainless meltUsually combined with nickel
- 5 ProductsSheet, tube, cutlery and process plant