Australian rare earths to a magnet in a motor

Australia · Mount Weld, Western Australia détenu par Lynas Rare Earths (Mineur)

Mining a natural concentrate

Open-pit mining of deeply weathered carbonatite. Weathering has already done much of the concentrating work over geological time.

Pourquoi ici: Carbonatite pipes are rare, and ones with a thick weathered cap are rarer still.

Australia · Mount Weld concentrator détenu par Lynas Rare Earths (Mineur)

Flotation to a concentrate

Milled and floated to a mineral concentrate at roughly 40% rare-earth oxide.

Ce qu'il est advenu du reste: 980 tonnes of tailings, on site, in Australia.

Pourquoi ici: Concentrate at the mine, always.

Malaysia · Fremantle to Kuantan, Malaysia détenu par Lynas Malaysia (Affineur)

First border crossing

Concentrate is shipped to Malaysia, where the plant that cracks it was built.

Pourquoi ici: The cracking and separation plant was permitted and built here rather than in Australia — a decision about chemistry, cost and permitting that took years and remains contested.

Malaysia · Kuantan, Pahang détenu par Lynas Malaysia (Chimique)

Cracking it open with acid

Roasted with concentrated sulfuric acid to break the mineral apart, then leached. Thorium and uranium that came with the ore have to be separated and managed here.

Ce qu'il est advenu du reste: The radioactive residue is the reason this step is hard to permit anywhere, and the reason so few countries have it.

Pourquoi ici: Because someone was willing to build it and see it through.

Malaysia · Separation plant détenu par Lynas Malaysia (Affineur)

Hundreds of stages to tell them apart

Solvent extraction through hundreds of mixer-settler stages, exploiting differences in ionic radius so small they are almost invisible. Out come separated oxides: neodymium-praseodymium, lanthanum, cerium.

Ce qu'il est advenu du reste: Cerium and lanthanum come out too, in larger quantities than anyone wants them. Surplus light rare earths are the industry's structural problem.

Pourquoi ici: This is the hardest step in the chain and the one with the fewest operators worldwide.

China · Metal and alloy plants détenu par Metal and magnet makers (Fabricant)

Oxide to metal to alloy

The oxide is reduced to metal by molten-salt electrolysis, then strip-cast with iron and boron into a rapidly-quenched NdFeB alloy ribbon.

Pourquoi ici: Metal-making capacity outside China is very small. This is the step a Western mine cannot yet route around.

China · Ningbo or Ganzhou détenu par Magnet manufacturer (Fabricant)

Making the magnet

Hydrogen decrepitation, jet milling to a few microns, pressing in a magnetic field to align the grains, sintering, machining, and a nickel-copper-nickel coating so it does not corrode. Dysprosium or terbium is diffused into the grain boundaries so it survives heat.

Ce qu'il est advenu du reste: Machining swarf is recycled internally — magnet scrap is one of the few genuinely closed loops in this industry.

Pourquoi ici: Roughly 30% of a sintered magnet's mass is rare earth. This is where the ore finally becomes a component.

Germany · Motor and vehicle plants détenu par Motor and vehicle manufacturers (Fabricant)

Into a traction motor

1.6 tonnes of magnet is on the order of two thousand car traction motors, or the generator of a single large offshore wind turbine.

Pourquoi ici: Four countries, three oceans, five processing steps — from one tonne of Australian rock to the thing that makes an electric car move.