Lanthanum through gadolinium. These are generally more abundant.
The REE market is characterized by high geographical concentration. For decades, China has dominated the global supply chain, controlling a vast majority of both mining and processing capacity. This has raised significant economic and national security concerns for other nations, leading to a global push to diversify sources, reopen mines (like Mountain Pass in the U.S.), and invest in recycling technologies. 4. Environmental Impact The Rare Earth Elements: An Introduction
Chemically, REEs are known for their similar ionic radii and oxidation states (usually +3), which causes them to occur together in mineral deposits. This similarity makes the chemical separation of individual elements a complex and energy-intensive process. 2. Critical Applications Lanthanum through gadolinium
Terbium through lutetium, plus yttrium. These are rarer and often more valuable due to their specific high-tech applications. For decades, China has dominated the global supply
REEs are the "vitamins" of modern industry—required in small amounts but essential for performance.