Rare earth elements (REEs) comprise a group of 15 elements known as the lanthanides in the periodic table. Scandium and yttrium are commonly included due to their similar chemical properties and their occurrence in the same types of mineral deposits.

REEs are typically classified into light rare earth elements (LREEs)and heavy rare earth elements (HREEs). This classification reflects differences in atomic structure, geochemical behaviour, abundance, and industrial relevance. Light rare earth elements are generally more common in the Earth’s crust, whereas heavy rare earth elements are less abundant and often more challenging to source.

Rare earth elements play a critical role in a wide range of modern technologies. They are essential components in consumer electronics such as smartphones, displays, audio devices, and optical systems. High-performance rare earth magnets are key to wind turbines, electric and hybrid vehicles, and energy-efficient motors. REEs are also widely used in industrial catalysts, rechargeable batteries, and defence and guidance systems.

Due to their importance in clean energy technologies and advanced industrial applications, rare earth elements are increasingly recognised as strategically important raw materials.