Scandium
A rare-earth metal that strengthens aluminium alloys and stabilises solid-oxide fuel cells, produced only as a by-product in tiny volumes.
Tech & minor metals · No. 48
- EU critical 2023
- US critical 2025
The world makes only about 80 t of scandium oxide a year, yet a few tenths of a percent transforms aluminium.
Chart: Illustration: Scandium
Where it comes from
Chart: Map of where it comes from
No mine produces scandium as its main product. It is recovered from nickel and titanium process streams and old tailings, then calcined to oxide; about 80 t was made in 2025.
Three things to know
- A few tenths of a percent scandium forms fine Al3Sc particles in aluminium, raising strength and letting it be welded without cracking.
- In zirconia, scandia gives the highest oxygen-ion conductivity, which is why solid oxide fuel cells use it.
- Australia reports about 34,000 t of scandium in accessible resources, of which 12,000 t meet JORC reserve standards.
The journey
- 1 Process streamsNickel, titanium or uranium residues, tailings
- 2 LeachingSolvent extraction pulls out scandium
- 3 OxalatePrecipitated as scandium oxalate
- 4 OxideCalcined to 99.99% scandium oxide
- 5 Alloy or metalAl-Sc master alloy with 2% Sc
- 6 End usesAerospace alloys and fuel-cell electrolytes