What are rare earths? Complete list, where they are found and what they are used for

What are rare earths, so fundamental to the present and future economy? Still little known to the general public, rare earths are today one of the causes of major geopolitical tensions worldwide.
Although the name may be misleading, rare earths (REEs in English, acronym for Rare Earth Elements) are a set of 17 metallic elements.
These include the 15 lanthanides of the periodic table plus scandium and yttrium.
Let's see in detail what rare earths are, the complete list, where they are found, what they are used for and why they play a prominent role in the energy transition.
Complete Guide to Rare Earths What are Rare Earths? The complete list of rare earths What are rare earths used for? Why are they called rare earths? How are rare earths extracted? Where are rare earths found? Who produces rare earths? The role of rare earths in the energy transition What are rare earths? What do we mean, then, when we talk about rare earths? In detail, this is the collective name used to indicate 17 chemical elements present in the famous periodic table.
Of these 17 elements, 15 are lanthanoids (elements that have an atomic number between 57 and 71), while the remaining two are scandium and yttrium (atomic numbers 21 and 39, respectively).
Rare earths are further divided based on atomic weight into: light rare earths (LREE), medium rare earths (MREE), heavy rare earths (HREE).
Rare earths, contrary to what one might think, are relatively abundant in the earth's crust.
However, due to their geochemical properties, these are generally dispersed.
This means that it is difficult to find clusters that are sufficiently concentrated to make them usable for mining.
It was the scarcity of these minerals that led them to be called “rare earths”.
Rare earths are classified into light elements (from lanthanum to samarium) and heavy elements (from europium to lutetium).
The latter are less widespread and consequently more expensive.
Chemically, rare earths are strong reducing agents.
Their compounds are generally ionic and have high melting and boiling points.
Rare earths are relatively soft when in their metallic state, while those with a higher atomic number tend to be harder.
Rare earths react with other metallic and non-metallic elements to form compounds, each of which has specific chemical behaviors.
This makes them indispensable and non-replaceable in many electronic, optical, magnetic and catalytic applications.
Rare earth compounds commonly fluoresce under ultraviolet light, which can aid in their identification.
Rare earths also react with water or dilute acid to produce hydrogen gas.
The complete list of rare earths Below, the complete list of the 17 rare earths, accompanied by their chemical symbol and relative atomic number (Z).
Atomic numberSymbolName 21 Sc Scandium 39 Y Yttrium 57 La Lanthanum 58 Ce Cerium 59 Pr Praseodymium 60 Nd Neodymium 61 Pm Promethium 62 Sm Samarium 63 Eu Europium 64 Gd Gadolinium 65 Tb Terbium 66 Dy Dysprosium 67 Ho Holmium 68 Er Erbium 69 Tm Thulium 70 Yb I tterbium 71 Lu Lutezio read also Rare earths, the Chinese squeeze is coming What are rare earths for? A more in-depth analysis of rare earths helps us understand their preciousness in meeting the needs of our daily lives.
These elements play a primary role in hardening, lightening and adding strength, lightness, magnetic and conductive properties to alloys.
With some rare earths, electric car engines have more efficient performance.
Furthermore, they are necessary for the operation of wind turbines, smartphones, medical instruments and even some types of missiles.
Europium, for example, is present in low-energy LED light bulbs and erbium is essential for laser applications and in optical fibers.
The main peculiarity of rare earths lies in the magnetism resistant to high temperatures: for this reason they are indispensable in the production of technological products, but not only.
One of the fields in which the use of these raw materials is most requested is the military sector, where the 17 earth elements are indispensable for the production of the so-called "directed energy weapons": a class of armaments that includes numerous devices capable of directing various forms of non-kinetic energy on targets.
Essentially, these devices send electromagnetic radiation, acoustic waves, high-energy plasma or laser beams onto the target to be hit.
Rare earths have also historically been essential to the petrochemical industry in breaking down large molecules into smaller hydrocarbons suitable for use in fuels.
Below is a table listing the major use cases of rare earths divided by element: Rare earthWhat is it for? Yttrium Phosphorus, ceramics, metal alloys Lanthanum Batteries, catalysts for petroleum refining Cerium Autocatalysts, chemical catalysts, glass polishing, metal alloys Praseodymium High power magnets, yellow ceramic pigment Neodymium High power magnets Promethium Radiation source Beta Samarium Magnets for high temperatures Europium Fluorescent lighting Gadolinium MRI contrast agent, nuclear fission moderation bars Terbium Phosphorus for illumination, high power, high temperature magnets Dysprosium High temperature, high power magnets, lasers Holmium Highest power magnets available in the world Erbium Laser, colorant for glass Thulium Magnetic ceramic materials, still under development Ytterbium Fiber optic technology, solar panels Lutetium PET scanner Why are they called rare earths? We must not be fooled by the adjective "rare": these elements are not at all scarce in the world and this qualification does not, in fact, derive from the quantity on the planet.
The diffusion of some of the 17 elements is equal to that of copper or lead.
Specifically, cerium is the 25th most abundant element on earth with 68 parts per million.
This makes it as abundant as copper.
Rarity, therefore, is linked to another concept, namely their low concentration in mineral deposits.
How are rare earths extracted? In their natural state, rare earths are found mixed with other minerals, usually in small quantities.
As a result, extracting them is very difficult and requires a rather complex process.
Starting from the extraction or separation from an amalgam of rock and minerals, metals are then formed, combined into alloys and magnets.
All with a metal processing, refining and purification process that consumes a lot of heat, requires acid, and several thousand cycles.
For example, to obtain one kilo of vanadium you need to purify eight and a half tons of rock, which becomes 50 tons for one kilo of gallium and even 200 tons for one kilo of lutetium.
All this means releasing radioactive water, waste gases and other toxic waste.
Where are rare earths found? According to the United States Geological Survey, the country richest in these resources in the world is China.
The dragon, which owns about a third of the world's reserves or 40%, remains the global leader in possession of rare earths.
Beijing is followed by Vietnam and Brazil, Russia, India, Australia, Greenland and the United States.
China, however, also boasts control of production, thanks not only to the presence of the elements in its territory.
The Chinese leadership has also built on less severe laws regarding respect for the environment on widespread know-how.
According to the authoritative Geological Society of London, in terms of percentage in the Earth's continental crust, cerium is the most abundant, with 43 parts per million (ppm), followed by lanthanum (20 ppm) and neodymium (20 ppm), while l The rarest rare earth element is thulium (0.28 ppm), with the exception of promethium, which is practically absent due to its radioactivity.
Their abundance, therefore, is comparable to other important elements such as lithium (17 ppm), copper (27 ppm), tin (1.7 ppm) and uranium (1.3 ppm).
Who produces rare earths? Over the years, China has guaranteed itself a substantial monopoly in the global supply of rare earths, especially due to its production and refining capacity.
Bayan Obo, a region in northern China, is the largest rare earth deposit in the world.
Made up of three main mineral bodies and extending for 18 km in length, Bayan Obo accounts for 50% of China's rare earth production.
Other smaller deposits are found in Shandong, Sichuan, Jiangxi and Guangdong provinces.
Beijing controls 60% of global production of these elements and four-fifths of global refining.
Even if the minerals are extracted in the United States, to be used they require specific processes that only the dragon is able to offer.
In the USA there is the historic Californian Mountain Pass mine, which returned to operation in 2018 after various events and stops.
In 2020, it produced approximately 16% of the world's supply of rare earths.
And Europe? “In refining we are two-thirds dependent on China,” according to Luca Franza, head of the IAI's climate and energy programme.
Specifically, our continent produces just 3% of the world's total rare earths.
read also Rare Earths in Italy, where they are found and which mines can reopen The role of rare earths in the energy transition “The transition to a clean energy system is destined to lead to a huge increase in the need for…minerals, which means that the energy sector is emerging as a major force in mining markets”: this is how the International Energy Agency explains.
Among these resources that are increasingly necessary for the green revolution there are also rare earths.
For these they have become the dispute in the never-ending trade war between the USA and China.
In a scenario that meets the goals of the Paris Agreement, total demand for rare earth elements is expected to grow by 40% in just 20 years.
Not only that, World Bank estimates speak of a 500% jump in the production of minerals and metals by 2050.
The UN estimates that a total of 3 billion tonnes, of which 600 million tonnes of rare metals will be needed in decades.
The push for the energy transition is setting in motion the race for the fuel of the future.
If the industrial revolution was possible thanks to coal and the industrialization of the USA and beyond in the twentieth century saw oil as the engine, now the high-tech and green future will also be fueled by rare earths.
The development of new electric cars and the technologies to produce and exploit solar and wind energy depend on these 17 elements.
For example, rare earths are essential for making efficient, easy-to-maintain direct-drive wind turbines for large-scale offshore installations.
In the automotive sector, motors with rare earth permanent magnets are considered the preferred choice for electric vehicles.