実際に動いているもの
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.
- 素材
- Dysprosium
- 種類
- Ion-adsorption clay, very low grade, unusually rich in heavy rare earths
- 起点
- China — Weathered granite hills in Jiangxi, Guangdong and Fujian
工程ごと、越境地点ごとに
China · Jiangxi and Guangdong 保管者 State-consolidated producers (国営生産者)
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.
残りはどうなったか: Older, uncontrolled in-situ leaching left serious groundwater and slope-stability damage, which is much of why the industry was consolidated under state control.
なぜここか: 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 保管者 Producers (化学)
Precipitating a mixed carbonate
The pregnant solution is precipitated into a mixed rare-earth carbonate — the intermediate everything downstream starts from.
なぜここか: Concentrating before transport, as always.
China · Ganzhou, Jiangxi 保管者 China Rare Earth Group and affiliates (精製業者)
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.
残りはどうなったか: 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.
なぜここか: Heavy separation capacity is concentrated here to a degree unmatched by any other material in this atlas.
China · Magnet plants 保管者 Magnet manufacturers (製造業者)
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.
残りはどうなったか: This is substitution by engineering rather than by chemistry — same performance, a fraction of the scarce element.
なぜここか: Grain-boundary diffusion is a process advantage held by a small number of manufacturers.
Germany · Traction motors and turbines 保管者 Motor manufacturers (製造業者)
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.
なぜここか: A few kilograms of a metal from a Chinese hillside is what lets an electric motor survive a summer traffic jam.
これは計算例である。公表された標準的な歩留まりと回収率を用いて、明示された出発量を追うものであり、比率は検証可能だが、特定の荷物の記録ではない。経路に関する事実——どの国を経由するか、どのような工程を経るか、なぜその素材を他の場所では処理できないか——は公開情報から編集している。