The scarcer, higher-atomic-weight rare earths, including dysprosium and terbium.
The heavier elements in the rare earth series, including europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium. HREEs are more valuable and scarcer than light rare earths, critical for high-performance magnets and advanced technology.
Heavies are far less abundant than the light rare earths and command much higher prices, because the magnet metals that survive heat are found here. A deposit with a meaningful heavy split is disproportionately valuable.
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