Rare earth metals have become a major media topic as demand for them grows for everything from smartphones to wind turbines, and governments look to secure supplies.
Here are some key facts about them:
WHAT ARE THEY?
Rare earth metals are a group of 17 elements - 15 silvery-white metals called lanthanides or lanthanoids, plus scandium and yttrium.
WHAT ARE THEY USED FOR?
They are used in a wide range of products, including consumer electronics, electric vehicles (EVs), aircraft engines, medical equipment, oil refining, and in military applications such as missiles and radar. systems.
WHICH COUNTRY IS THE LARGEST PRODUCER?
China accounts for about 60% of the world's output and 90% of the production of processed and permanent magnets. Beijing sets quotas for extraction, smelting and separation, which are closely monitored, as they are a barometer of global supply.
WHAT ARE THEIR NAMES?
In order of the periodic table, they are: scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium.
WHICH OF THEM ARE THE MOST COMMON?
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 that reduce emissions in internal combustion engines.
Neodymium and praseodymium are sought after for permanent magnets used in electric vehicle motors and wind turbines.
ARE THEY RARE?
They are not rare in the sense that they are rare—some are more common than lead, for example—but they are usually found in small quantities in the Earth's crust, often as a combination of several such elements and found together with other minerals, so larger deposits are difficult to find and expensive to extract.
WHAT IS THEIR IMPACT ON THE ENVIRONMENT?
The processing of rare earth elements often involves the use of solvents, which can lead to the formation of toxic waste that pollutes the soil, water, and atmosphere. More environmentally friendly technologies are currently being developed, but they are not yet widely used.
Some types of rare earth ores also contain radioactive thorium or uranium, which are often removed using acid.
For this reason, the development of the sector is associated with health and environmental regulatory obstacles.