WHEN the early craftsmen first observed that the metals they worked in were made harder by hammering, and that the original softness could be again restored to the hardened metal by heat, it ...

Light metals, by contrast, have a lesser atomic weight. The two most important are neodymium and praseodymium, which are primarily used to create magnets. What are they used for?

Lanthanum and cerium are among the most common rare earth metals. Lanthanum is used in camera lenses and lighting. Cerium is used in catalytic converters, which reduce combustion engine emissions.

As geopolitical and trade tensions rise, China’s dominance of both mining and processing means these niche metals have become a cudgel to use against opponents. Skip to content.