What is actually moving
Heavy rare earths do not come from a conventional orebody. They come from weathered granite where the metal ions cling loosely to clay, and they are recovered by washing a salt solution through the hillside. The grade is tiny; the strategic weight is enormous.
- The material
- Dysprosium
- The variety
- Ion-adsorption clay, very low grade, unusually rich in heavy rare earths
- Where it starts
- China — Weathered granite hills in Jiangxi, Guangdong and Fujian
Step by step, and border by border
China · Jiangxi and Guangdong held by State-consolidated producers (State producer)
Leaching the hill in place
Ammonium sulfate solution is injected into the weathered granite and collected downslope. The rare-earth ions swap places with ammonium on the clay and come out in solution. Nothing is blasted and, in modern practice, little is dug.
What happened to the rest: Older, uncontrolled in-situ leaching left serious groundwater and slope-stability damage, which is much of why the industry was consolidated under state control.
Why here: This deposit type needs a specific granite, a specific climate and millions of years. It is not a matter of looking harder elsewhere.
China · On site held by Producers (Chemical)
Precipitating a mixed carbonate
The pregnant solution is precipitated into a mixed rare-earth carbonate — the intermediate everything downstream starts from.
Why here: Concentrating before transport, as always.
China · Ganzhou, Jiangxi held by China Rare Earth Group and affiliates (Refiner)
Separating the heavies
Solvent extraction, but far harder than for the light rare earths: dysprosium, terbium, holmium and erbium are even more alike than neodymium and praseodymium, so it takes more stages and more patience.
What happened to the rest: Terbium, yttrium, gadolinium and the rest come out alongside. Yttrium is by far the largest fraction; dysprosium and terbium are the ones everyone actually wants.
Why here: Heavy separation capacity is concentrated here to a degree unmatched by any other material in this atlas.
China · Magnet plants held by Magnet manufacturers (Manufacturer)
Diffused into a magnet's grain boundaries
Rather than alloying dysprosium throughout the magnet, it is painted on and diffused into the grain boundaries where it does the most good. The technique cut dysprosium use per magnet several-fold.
What happened to the rest: This is substitution by engineering rather than by chemistry — same performance, a fraction of the scarce element.
Why here: Grain-boundary diffusion is a process advantage held by a small number of manufacturers.
Germany · Traction motors and turbines held by Motor manufacturers (Manufacturer)
A motor that can get hot
Without dysprosium a neodymium magnet begins losing strength around 80 °C. A traction motor or a turbine nacelle routinely runs hotter than that. 15 kg is enough for several thousand car motors.
Why here: A few kilograms of a metal from a Chinese hillside is what lets an electric motor survive a summer traffic jam.
This is a worked example. It follows a stated starting quantity through published typical yields and recoveries, so the proportions are checkable; it is not a record of a specific shipment. Route facts — which countries, which processes, and why the material cannot simply be handled somewhere else — are compiled from public reporting.