Under human, animals and insects that have walked this earth for aeons are elements that have always been there but the properties or potential uses were not fully understood, until fairly recently.

Gold, Silver, Copper and Iron each have had separate ‘ages’ in the evolution of humankind, as each element was discovered a use for it was found. Lead [Pb-82] was one of the first metals discovered due to its abundance, the ancient Romans in 3000 BC used it to make then seal water pipes and to line baths, even now the name ‘Plumber’ takes its name from the Latin for Plumbum, meaning Lead.

Throughout history even into the dark ages and still now, alchemists, chemists, engineers and scientist have combined metals to create alloys, stronger versions of not one but a combination of mixed metals, they had better crystalline structures and properties meaning added strength, different metal could be mixed together to save weight and therefore create lighter tools including battle borne implements – with ancient history and alchemy, lead was considered the “Prima Matera” (Primal Matter).

As time went past more and more elements were discovered, some purely by accident and others after being theorized then being actively searched for. In 1869, the Russian inventor and chemist Dmitri Mendeleev used the ‘Periodic law’ to correct classification errors in the then known properties of discovered elements such as that of the valence and atomic weight of Uranium – back then there were just 63 elements that had been discovered and classified – he then predicted another 8 elements that were not discovered yet, classifying and placing them by atomic weight in his extended version of the periodic table we know today. These were the early days of modern science and as such we should not forget the work of early chemists and scientists like Medleleev and other notable individuals.

I saw in a dream a table where all elements fell into place as required. Awakening, I immediately wrote it down on a piece of paper, only in one place did a correction later seem necessary.

- Dmitri Mendeleev (as quoted by Inostrantzev).

The rare earth elements we are referring to are actually all metals, 15 elements are in the Periodic Table group called Lanthasides and there another two additional elements that share very similar chemical properties – they are plentiful in nature but hard to come by as well as being hazardous to human health (and costly) to extract, they are crucial to the manufacturing of many high-tech products – a modern smartphone can contain up to 62 different types of metals including those of rare earth elements.

There are 17 known rare earth elements that are spread very evenly over the earth’s surface making it had to find large deposits in one place but often rare earth elements are found grouped together, there could well be more that are vital to technological developments in the future but are as yet still undiscovered, as of now due to their unique magnetic, luminescent, and electrochemical properties many tech sectors use these elements for reduced weight in alloys, higher thermal limits, reduced energy consumption, speed, durability and they even prolong and save lives, listed below are the rare earth elements by Alphabetical listing with the Periodic Table classification symbol and atomic number referenced too:

Cerium [Ce-58]

A component of ‘mischmetal’ that is itself a mixture of rare earth metal and is used for the manufacture of lighters flints, allows catalytic converters in road vehicles to run at high temperatures, it is also used in the refining process of crude oil. Cerium oxide is used for incandescent gas mantles and as a catalyst in self-cleaning ovens. It also has uses in precision glass polishing as in the manufacture of the Hubble space telescope reflecting mirror,it has its uses in iron, magnesium and aluminium alloys, in magnets, some types of electrolytes and carbon-arc-lighting too.

This is the most abundant of the rare earth elements and named for the Roman goddess of nature, it makes up about 0.0046% of the earth’s crust.

Dysprosium [Dy-66]

This metal has one of the highest magnetic strengths of the elements, it is added to rare earth magnets like those in Tesla car electromagnetic motors to help them operate more efficiently and safely at high temperatures by preventing shattering or chipping of the layers. Some lasers and commercial lighting systems use Dysprosium as well as computer hard drives and electronics that require certain magnetic properties. It is also used in some nuclear reactors.

There is a shortage of this element but manufacturing processes have learnt to use less of this material, mainly with the key component areas required rather than complete coverings.

Europium [Eu-63]

A good absorber of neutrons, Europium has found uses in nuclear reactors, conversely, it is a by-product of nuclear fission and does not occur in a pure form in nature, it is radioactive but less so than Caesium and Strontium. Europium oxide (Eu2o3), one of Europiums compounds is widely used in TV sets as a red phosphor as well as an activator for Yttrium-based phosphors. It is also used as a special phosphor to create marks on Euro notes to help prevent counterfeiting.

Erbium [Er-68]

Another rare earth elements that’s important in nuclear applications, like Europium it is a good absorber of neutrons and as such can be found in ‘control rods’ within nuclear reactors, it is also a very important component in high-performance fiber optic communication systems, it can also be used to give glass and other materials a pink colour for both aesthetic and industrial purposes. Erbium is also used in the creation of some medical lasers for patient treatment and laboratory purposes.

Gadolinium [Gd-64]

This element is very important for functions such as offering safety shielding from radiation in highly reactive nuclear reactor cores, it is also used for medicinally in radiation (neutron) therapy to target tumours and further still within MRI (Magnetic resonance imaging) whole-body scanning machines to improve diagnostic accuracy (it improves the visibility of blood vessels, organs, inflammations, tumours and blood supply in some organs). It can assist with the detection and then further treatment of some cancerc and has found other uses for X-Ray and bone density tests making it a major contributor to modern health care systems.

Holmium [Ho-67]

Along with Dysprosium, Holmium has incredible magnetic properties, some of the strongest artificially created magnetic fields are as a result of Holmium alloys to create magnetic flux concentrators. This element is used in nuclear reactor control rods and microwave equipment, it can also be used to provide a special pink colouring for glass and Zirconia.

Lanthanum [La-57]

Used for camera and telescope lenses as a coating due to its low refractive with Infra-red absorbing properties, it is also used in some arc lighting and even as a material for lighter flints (25% – 40% overall content), it is using in many swimming pool treatments to prevent algae as well as in the medical sectors with renal treatment and as an electron-trace denser in microbiology.

Lutetium or [Lu-71]

Lutenin has some interesting and diverse uses, Lutenium isotopes can be used to date ancient items including meteorites, there are also applied sciences within the petroleum refining industry and is used in PET (Positron emission tomography) scans that measures the metabolic activity within cells in body tissues. )PET is a combination of biochemical analysis and nuclear medicine, it has been used experimentally in the targeting and treatment of cancerous tumours).

Neodymium [Nd-60]

Used in the construction of powerful (rare earth) magnets for loudspeakers and computer hard drives enabling them to be smaller and more efficient, they are also used in wind turbines for green energy also in the production of Hybrid and fully electric vehicle motors.

Praseodymium [Pr-59]

The primary use of this metal is as an alloying agent, when mixed with magnesium it creates high strength metals for use in aircraft engines, it is a highly sought after element that has special chemical, electrical, magnetic and optical properties.

Promethium [Pm-61]

This is the only naturally radioactive rare earth element, most of the Promethium deposited in the earth crust has decayed into other elements, some deposits are still to be found but in very small amounts, for today’s industrial manufacturing requirements it is artificially created and used in watches, pacemakers as well as for scientific research.

Samarium [Sm-62]

This elemental metal has very powerful magnetic properties that it is widely used in transportation, commercial and defence technologies. Samarium is used with other medicinal compounds to target and treat cells with lung, breast and some form of bone cancers. As it is a stable neutron absorber the metal is used in nuclear power ‘control rods’.

Scandium [Sc-21]

Scandium is used in aluminium-scandium alloys for aerospace industry components, the alloy components were actually dreamt up by massive cloud computing and Artificial Intelligence scenarios, it is also used for down to earth application like sports equipment such as tennis rackets, fishing rods, bicycle frames and even baseball bats to strengthen metal compounds. Scandium iodide replicates sunlight for the film and television industry in mercury vapour lamps.

Terbium [Tb-65]

Discovered in 1843, Terberium has the highest magnetostriction of the rare earth elements in its alloy form, this means that it’s shape changes more than any other substance. It is commonly is used in Compact Fluorescent Lighting (CFL), mixed as an additive for rare earth magnets allowing them to perform better at higher temperatures, it has also found its way into electronic devices and naval sonar systems.

Thulium [Tm-69]

One of the least abundant rare earth elements, it is a component of highly efficient laser systems as well as being the radiation source in portable X-ray machines and other uses are being found medicinally like those of ‘Laser-Knifes’ to target and break down kidney stones. It is also used in meteorology applications.

Yttrium [Y-39]

The widest use of this element is as its oxide, Yttria Y2o3 and have been used since the 1970s for making red phosphor in colour TV tubes, those old TVs are not made anymore but smartphones and flat-panel devices utilise it now. It can be used with some other metals like aluminium and magnesium to create stronger alloys. There are other uses such as that of cancer treatment drugs, high powered pulse lasers, rheumatoid arthritis medicines, superconductors and as a coating on digital camera lenses.

Ytterbium [Yb-70]

This element has found uses being alloyed with stainless steel to improve some of its mechanical properties, it is used as a doping agent to amplify fiber optic cables, like some of the other rare earth elements it is used in the medical sectors including dentistry work as well as being a stable source for X-Ray machines in areas where electricity is not available, it is also used for some anti-cancer treatments.

The rare earth elements are important contributors to the world and its population for health, safety and comfort, without these elements the advancement of modern technological achievements would not have been possible.