This graphic looks at the elements known as the lanthanides – the ones stranded at the bottom of the periodic table, along with the actinides. For a group of elements that doesn’t really get much attention in chemistry teaching until at least undergraduate level, their applications are remarkably widespread and varied. Most modern electronic devices rely on rare earth elements in some part of their construction, so it’s remarkable that the average person on the street will probably have little to no knowledge of their importance.
The concern when it comes to rare earth metals is their supply. The term ‘rare earths’ is actually something of a misnomer, since the abundance of some of the lanthanides is in fact greater than some of the transition metals. Nonetheless, the surge in the various applications of these elements has seen rare earth supplies being progressively depleted; the US, for example, is now almost 100% reliant on imports of rare earth elements. China is currently the world’s main source of these elements, but they believe that two thirds of their supplies have already been mined. This is problematic because for many applications rare earths are the best choice by some distance; in electronic devices, for instance, ceasing to use rare earth elements would mean a return to performance standards years previous.
As well as the uses noted in the graphic, the lanthanides have applications in catalysis, electronic polishing, glass polishing, night vision goggles, welding visors, and lasers.